megasquirt2 setting up-3.4

8/16/2019 Megasquirt2 Setting Up-3.4

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Megasquirt-2 Setting upMegasquirt-2 Product Range

MS2/Extra 3.4.x

Dated: 2015-07-10

Instructions for setting up your Megasquirt-2 ECU.

This version of the documentation applies to the Megasquirt-2 range of products hich includes!

• MS2 on "3.# or "3.$% main&oard'

• MicroSquirt'

• (roducts derived from the MicroSquirt Module )e.g.* +,(( and MS((2.

and running firmare MS2/Extra 3.4.x. )See section 2.0#.3 for more detail on version num&ers.

ot covered!

• Megasquirt-2 products running 1oling and rippo1 firmare.

• Megasquirt-2 products on a "2.2 main&oard.

• MegaSquirt-0'

• EMS-(ro

• MegaSquirt-3'

• MS3-(ro or products using MS3-(ro module

• MS3-old

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Megasquirt-2 Setting 6p #!7uic8Start uide - in &rief

0: QuicStart !uide - in "riefThis list is provided as the &are essentials that 5ou #ust read. 9ull details of each step are provided ithinthe &od5 of the manual.

0. u5 or &uild 5our Megasquirt:

2. Select and assem&le 5our fuel and ignition s5stems.

3. Setup 5our vehicle iring harness ensuring it is fused.

4. ;onnect M<( hose to full vacuum source. )Speed +ensit5 onl5.

$. ,nstall TunerStudio and Megalogvieer softare onto 5ou computer.

=. ;onnect 5our Megasquirt to a 02" fused suppl5 either in the vehicle or on the &ench.

%. et the serial comms set up.

>. ,nstall the firmare if required.?. et 5our tuning computer to tal8 to the E;6.

0#. Setup sensor cali&rations to match hardare. )T(S* @2 sensor* temp sensors.

00. ;hec8 all sensor inputs are reading sensi&l5 in TunerStudio.

02. Set the &ase settings )engine t5pe* ignition setup* toothed heel t5pe.

03. 6se the test mode to confirm inAectors and coil)s are functioning.

04. ;hec8 for B(M input.

0$. ;hec8 the cran8ing timing ith fuel disa&led.

0=. Start the engine and start tuning.

<ll parts are sold for @99 B@<+ B<;E-@C ground-vehicle use onl5 - see section 0.0 for more details.

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Megasquirt-2 Setting 6p #!;ontents

0: Contents

$a"%e of C&apters

#! 7uic8Start uide - in &rief..................................................................................................2#! ;ontents.............................................................................................................................30! ,ntroduction.........................................................................................................................?2! 7uic8Start uide - expanded...........................................................................................033! Tuning the engine.............................................................................................................4=4! <dvanced topics...............................................................................................................=$$! Trou&leshooting................................................................................................................>==! <ppendix <! 9irmare upgrade notes..............................................................................?%%! <ppendix ! 9uel calculations........................................................................................0#4>! <ppendix ;! Megasquirt lossar5 of Terms...................................................................0#=

?! Bevision histor5..............................................................................................................003

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Contents

#! 7uic8Start uide - in &rief..................................................................................................2#! ;ontents.............................................................................................................................3

0! ,ntroduction.........................................................................................................................?0.0 Emissions and disclaimer............................................................................................?0.2 Bequired tools..............................................................................................................?0.3 Do to use the manuals..............................................................................................?0.4 (roducts ;overed......................................................................................................0#

0.4.0 MS2 on "2.2 main&oard.....................................................................................0#0.4.2 MS2 on a "3.# main&oard..................................................................................0#0.4.3 MS2 on a "3.$% main&oard................................................................................000.4.4 Microsquirt..........................................................................................................000.4.$ Microsquirt-module.............................................................................................02

0.$ ;op5rights..................................................................................................................022! 7uic8Start uide - expanded...........................................................................................03

2.0 u5 or &uild 5our Megasquirt:....................................................................................032.2 Select and assem&le 5our fuel and ignition s5stems.................................................032.3 Setup 5our vehicle iring harness )loom ensuring it is fused..................................032.4 ;onnect M<( hose to full vacuum source.................................................................032.$ ,nstall TunerStudio and Megalogvieer.....................................................................032.= (oer up 5our E;6...................................................................................................032.% et the serial comms set up......................................................................................032.> Turn off 1Dide extensions for 8non files t5pes1 )indos @nl5.............................0=2.? ,nstall the firmare if required...................................................................................0%

2.0# et 5our tuning computer to tal8 to the E;6...........................................................2#2.0#.0 TunerStudio &asics...........................................................................................242.0#.2 9irmare* TunerStudio* tune files )MS7 - hatFs all thatG..............................2$2.0#.3 "ersion num&ers...............................................................................................2$

2.10.3.1 Mainboard version..................................................................................................25

2.10.3.2 Firmware Version...................................................................................................252.10.3.3 TunerStudio Version...............................................................................................26

2.10.3.4 MegaLogViewer Version........................................................................................262.10.3.5 Oerating s!stem version.......................................................................................26

2.00 Setup sensor cali&rations to match hardare.........................................................2=2.00.0 ;ali&rate T(S....................................................................................................2=

2.00.2 ;ali&rate M<(/aro..........................................................................................2%2.00.3 6nloc8 cali&rations............................................................................................2%2.00.4 ;ali&rate ;CT and M<T sensor.........................................................................2>2.00.$ ;ali&rate <9B ta&le )@2 sensor......................................................................2?2.00.= Coc8 cali&rations...............................................................................................3#

2.02 ;hec8 all sensor inputs are reading sensi&l5 in TunerStudio..................................3#2.02.0 M<( sensor chec8............................................................................................3#2.02.2 T(S chec8........................................................................................................3#

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2.02.3 ;CT sensor chec8.............................................................................................3#2.02.4 M<T sensor chec8............................................................................................3#2.02.$ @2 sensor chec8...............................................................................................3#2.02.= M<9 sensor chec8............................................................................................3#

2.02.% atter5 voltage chec8.......................................................................................3#2.03 Set the &ase settings...............................................................................................302.03.0 ;ontrol <lgorithm choice..................................................................................322.03.2 Engine and Sequential settings........................................................................332.03.3 ,nAector dead-time.............................................................................................332.03.4 ,gnition setup....................................................................................................342.03.$ ,dle "alve..........................................................................................................342.03.= @ther inputs/outputs.........................................................................................3$2.03.% auge/Setting Cimits........................................................................................3$2.03.> (oer ;5cle Bequired......................................................................................3$2.03.? ;onfiguration Error...........................................................................................3=

2.04 6se the test mode to confirm inAectors and coil)s are functioning.........................3%2.04.0 ,nAector testing..................................................................................................3%2.04.2 ;oil testing........................................................................................................3%2.04.3 9uel pump testing.............................................................................................3>2.04.4 ,dle "alve Testing..............................................................................................3>

2.14.4.1 "sing t#e test mode to determine steer #oming stes........................................3$

2.0$ ;hec8 for cran8/cam tach-in signals........................................................................4#2.0= ;hec8 for B(M input................................................................................................422.0% ;hec8 sensors during cran8ing...............................................................................422.0> Sample datalog........................................................................................................422.0? ;hec8 the cran8ing timing ith fuel disa&led..........................................................42

2.2# Start the engine and start tuning.............................................................................432.20 Bun engine up to temperature.................................................................................442.22 Setting running timing..............................................................................................44

3! Tuning the engine.............................................................................................................4=3.0 Do it or8s - fuel.....................................................................................................4=

3.0.0 ;ran8ing mode...................................................................................................4=3.0.2 Bun mode...........................................................................................................4=

3.2 Do it or8s - ignition................................................................................................4>3.2.0 ;ran8ing mode...................................................................................................4>3.2.2 Bun mode...........................................................................................................4>

3.3 Ta&les and curves......................................................................................................4?3.4 Tuning fuel.................................................................................................................4?

3.4.0 Tuning fuel - Speed +ensit5...............................................................................4?3.4.1.1 %F& tab'e (S)*.........................................................................................................4$

3.4.1.2 V+ tab'e (S)*...........................................................................................................50

3.4.2 Tuning fuel - (ercent aro..................................................................................$23.4.3 Tuning fuel - <lpha-..........................................................................................$23.4.4 Tuning fuel - M<9...............................................................................................$2

3.4.4.1 M%F trans,er -urve..................................................................................................52

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3.4.4.2 %F& tab'e (M%F*.....................................................................................................533.4.4.3 V+ trim tab'e (M%F*................................................................................................53

3.4.4.4 M%F'oad..................................................................................................................54

3.4.$ Tuning fuel - ,T.................................................................................................$4

3.4.5.1 T/ Load TS Swit-#oint urve...........................................................................553.4.5.2 T/ Load at TS Swit-#oint urve........................................................................553.4.5.3 %F& Tab'e (T/*.......................................................................................................55

3.4.5.4 V+ Tab'e (T/*.........................................................................................................55

3.4.5.5 T/ te-#ni-a'............................................................................................................55

3.4.= asic acceleration enrichment )<E tuning........................................................$%3.4.6.1 Main a--e' enri-# settings menu..............................................................................53.4.6.2 Timebased %--e'.....................................................................................................5

3.4.6.3 etting it dia'ed in....................................................................................................5

3.4.% Startup / armup fueling....................................................................................=#3.4..1 riming u'se............................................................................................................61

3.4..2 raning u'se..........................................................................................................613.4..3 %,terstart (%S+* er-entage adder............................................................................61

3.4..4 %,terstart (%S+* taer...............................................................................................61

3.4..5 7armu enri-#ment er-ent mu'ti'ier....................................................................613.4..6 utting it a'' toget#er................................................................................................61

3.$ Tuning spar8..............................................................................................................=23.= etting a good idle.....................................................................................................=3

3.=.0 ;orrect 9uel )mixture........................................................................................=33.=.2 ;orrect Timing....................................................................................................=33.=.3 ;orrect <irflo....................................................................................................=3

3.% +atalogging................................................................................................................=4

3.%.0 Starting a datalog...............................................................................................=43.%.2 Stopping a datalog..............................................................................................=4

4! <dvanced topics...............................................................................................................=$4.0 Sequential 9uel..........................................................................................................=$

4.0.0 ;onfiguration......................................................................................................==4.0.2 ,nAector timing.....................................................................................................==4.0.3 Sequential/Semi-sequential Timing....................................................................==

4.2 E@ ;ontrol..............................................................................................................=>4.2.0 Simple <lgorithm ith arro&and Sensor........................................................=>4.2.2 Simple <lgorithm ith ide&and Sensor...........................................................=>4.2.3 (,+ <lgorithm ith ide&and Sensor................................................................=>

4.3 an8el Botar5 Engines.............................................................................................=?4.4 ;losed-Coop ,dle........................................................................................................=?4.$ Enhanced <ccel Enrichment )E<E...........................................................................%0

4.$.0 Tuning E<E.........................................................................................................%24.= oost ;ontrol.............................................................................................................%3

4.=.0 Solenoid connection...........................................................................................%34.=.2 @pen-loop Tuning Tips.......................................................................................%$4.=.3 ;losed-loop Tuning Tips.....................................................................................%$

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4.% itrous @xide )2@..................................................................................................%=4.%.0 S5stem t5pes......................................................................................................%=4.%.2 ;onnection.........................................................................................................%%4.%.3 Tuning considerations........................................................................................%%

4.> "aria&le "alve Timing )""T* ";T* "TE;* "<@S...................................................%>4.? ;< us Expansion..................................................................................................%>4.?.0 ;< protocol......................................................................................................%>4.?.2 +evice-to-device.................................................................................................%>4.?.3 (assthrough.......................................................................................................%?4.?.4 ;< iring..........................................................................................................>#4.?.$ ;< settings and data t5pes..............................................................................>#

4.$.5.1 7M o''ing............................................................................................................0

4.$.5.2 )igita' orts..............................................................................................................0

4.$.5.3 7M oututs............................................................................................................04.$.5.4 %8%)s................................................................................................................1

4.?.= ;< roadcasting..............................................................................................>04.?.% Example Settings - perf ,@extender...............................................................>04.?.> Example Settings - other devices.......................................................................>2

4.0# Beading and +atalogging an <dditional Sensor......................................................>24.0#.0 iring................................................................................................................>24.0#.2 TunerStudio custom.ini.....................................................................................>24.0#.3 Coo8up ta&le .inc..............................................................................................>3

4.00 (rogramma&le @n/@ff @utputs................................................................................>44.00.0 itise operations.............................................................................................>4

$! Trou&leshooting................................................................................................................>=$.0 Besets........................................................................................................................>=

$.2 B(M-S5nc issues......................................................................................................>=$.2.0 Cost s5nc reasons...............................................................................................>%

$.3 oise 9iltering............................................................................................................>?$.3.0 oise filter...........................................................................................................?0$.3.2 Tach interrupt mas8ing.......................................................................................?0$.3.3 Tach period reAection..........................................................................................?2$.3.4 (olarit5 ;hec8....................................................................................................?2

$.4 ;ommunications issues.............................................................................................?35.4.1.1 7indows devi-e........................................................................................................$3

5.4.1.2 Ma- OS 9 devi-e.....................................................................................................$35.4.1.3 Linu: devi-e.............................................................................................................$4

$.4.2 Coop&ac8 test for serial or 6S-serial ca&le......................................................?4$.4.3 Coop&ac8 test to Megasquirt &oard )not Microsquirt.........................................?$$.4.4 ;omms test to Megasquirt / Microsquirt.............................................................?$

=! <ppendix <! 9irmare upgrade notes..............................................................................?%=.0 9irmare versions.....................................................................................................?%=.2 <lpha* &eta* release codeG hatFs the differenceG...................................................?%=.3 6pgrading from 3.3.x.................................................................................................?%=.4 6pgrading from 3.2.x.................................................................................................?>

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=.$ 6pgrading from 3.#.x or 3.0.x..................................................................................0##=.= 6pgrading from 2.0.#...............................................................................................0##=.% 6pgrading from MS2/.........................................................................................0#0=.> 6pgrading from MS0/Extra......................................................................................0#2

=.? 6pgrading from MS0 )&ase....................................................................................0#2%! <ppendix ! 9uel calculations........................................................................................0#4%.0 Terms 6sed..............................................................................................................0#4%.2 Speed +ensit5..........................................................................................................0#4%.3 .2 <lpha- )pure...................................................................................................0#4%.4 <lpha- )h5&rid.......................................................................................................0#4%.$ H&aro.......................................................................................................................0#$%.= M<9.........................................................................................................................0#$

>! <ppendix ;! Megasquirt lossar5 of Terms...................................................................0#=?! Bevision histor5..............................................................................................................003

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Megasquirt-2 Setting 6p 0!,ntroduction

': IntroductionThis manual covers general setup and configuration information that applies to the hole Megasquirt-2product range* it should &e used in conAunction ith the TunerStudio Beference uide and the Dardare

uide for 5our product.

1.1 Emissions and disclaimer

<ll parts are sold for @99 B@<+ B<;E-@C ground-vehicle use onl5* or vehicles that pre-date an5federal and state emissions control requirements. <ftermar8et E9,/EMS s5stems are not for sale or use onpollution controlled vehicles. <lteration of emission related components constitutes tampering under the 6SE(< guidelines and can lead to su&stantial fines and penalties. our countr5/state/district ma5 also havespecific rules restricting 5our tampering ith 5our vehicleIs emissions s5stem.

Bace parts are inherentl5 dangerous and ma5 cause inAur5 or damage if improperl5 modified or altered&efore use. The pu&lishers of this manual ill not &e held lia&le for and ill not pa5 5ou for an5 inAuries ordamage caused &5 misuse* modification* redesign* or alternation of an5 of our products. The pu&lishers ofthis manual ill not &e held in an5 a5 responsi&le for an5 incidental or consequential damages includingdirect or indirect la&or* toing* lodging* garage* repair* medical* or legal expense in an5 a5 attri&uta&le tothe use of an5 item in our catalog or to the dela5 or inconvenience caused &5 the necessit5 of replacing orrepairing an5 such item.

1.2 Required tools

Tuning laptop

Stro&oscopic timing light

Multi-meter )volts* ohms

Scredrivers

ire cuttersTerminal crimpers

Soldering iron and solder

Deat-shrin8 tu&ing

9ire extinguisher

Although not essential, the following are highly recommended:

@scilloscope or scope-meter or soundcard scope

Test light

(oer pro&e

1.3 How to use the manuals

The documentation for the Megasquirt-2 product famil5 is split across a num&er of manuals. The Setting up*TunerStudio and MegaCog"ieer uides are general and appl5 to all Megasquirt-2 products. The Dardaremanuals focus in detail on Aust one product to 8eep the specifics clear. e sure to chec8 that 5ou are usingthe manual that applies to 5our product:

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Megasquirt-2 Setting 6p

MicrosquirtDardare

MS2/"3.#Dardare

MS2/"3.$%Dardare

Microsquirt-Module+evelopers

uide

@ther E;6 variantshardare guide from

supplier

Megasquirt-2 TunerStudio BeferenceMegaCog"ieer Beference )(lanned

<s an a&solute minimum* ensure that 5ou have folloed all of the steps in the 7uic8start uide.

;ustomers ne to E9, or less experienced ith Megasquirt are strongl5 advised to read the manuals ingreater detail.

This guide includes a num&er of notes hich are indicated as follos!

This s5m&ol indicates an J,nformationK note.

This s5m&ol indicates a J;autionK note.

This s5m&ol indicates a JarningK note.

,nstalling or tuning 5our Megasquirt/Microsquirt incorrectl5 can potentiall5 cause damage to 5our engine* theE;6 or external hardare. arning notes indicate specific areas here 5ou need to exercise extreme care.

+o not rel5 on these arnings as 5our onl5 criteria for ta8ing care :

9or additional help and support* visit the e&site (((.#se)tra.co#

1.4 Products Covered

The Megasquirt-2 range of products all use the same processor at the core &ut are pac8aged differentl5 fordifferent mar8ets. The core configuration and setup is almost identical. There are minor differences in ignitionsettings and iring.

,t is important to understand exactl5 hich product 5ou have.

1.4.1 MS2 on V2.2 mainoard

<lthough technicall5 possi&le* the com&ination of a Megasquirt-2 daughtercard and a "2.2 main&oard is not

recommended. Dardare and iring are not co*ered in these manuals.

<rchive copies of the old e&-manuals availa&le at http!//.msextra.com/manuals/ms2manuals/ that dogive some information on using MS2 on a "2.2 main&oard.

1.4.2 MS2 on a V3.! mainoard

This com&ination uses a self-assem&led "3.# main&oard and a Megasquirt-2 daughtercard. This is aimed atthe +,er that ants the challenge of self-assem&l5 and gives flexi&ilit5 for future extension and modification.

5 customiLing* more inputs and outputs are availa&le than the Microsquirt. Supports lo-impedance

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http://www.msextra.com/

http://www.msextra.com/manuals/ms2manuals/#archive


http://www.msextra.com/manuals/ms2manuals/#archive




inAectors. ,ncludes an internal M<( sensor.

ot recommended in 8it form for customers afraid of a soldering iron.

The MS2/"3.# com&ination is often assem&led &5 su&-suppliers and re-sold to end-users as a completedE;6.

"3.# main&oard )inside

MS2 plug-in daughtercard )inside

Dardare and iring are covered in the MS2/"3 Dardare Manual.

1.4.3 MS2 on a V3."# mainoard

This com&ination uses a factor5-assem&led "3.$% main&oard and a Megasquirt-2 daughtercard. This isaimed at the customer that ants a cased Megasquirt-2 &ut prefers to &u5 pre-assem&led. The "3.$%main&oard has less flexi&ilit5 for future extension and modification. 5 customising* more inputs and outputsare availa&le than the Microsquirt. Supports lo-impedance inAectors. ,ncludes an internal M<( sensor.

"3.$% main&oard )inside

MS2 plug-in daughtercard

Dardare and iring are covered in the MS2/"3.$% Dardare Manual.

1.4.4 Microsquirt

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The Microsquirt is a full5 factor5-assem&led E;6 and uses an automotive grade <M(SE<C connector. Thisis aimed at the cost conscious customer that ants a Megasquirt-2 t5pe product in a professional case.There is no provision for internal modification and lo impedance inAectors are not directl5 supported.External M<( sensor required for most installs.

Dardare and iring are covered in the Microsquirt +ard(are guide.

1.4." Microsquirt$module

The Microsquirt-module is a component circuit &oard that allos manufacturers to create their on customE;6s such as +,autotuneFs MS((2 range.

Module )inside 5our E;6

<s there are variations in implementation &eteen E;6s utiliLing the module. ou need to refer to themanufacturerFs supplied documentation for iring and ignition settings in particular.

+etails of the module card are covered in the Microsquirt-#odu%e guide for de*e%opers.

Dardare and iring for complete E;6s &ased on the module are covered in your supp%iersdocu#entation.

1." Co%&ri'hts

This manual contains content cop5right 2#04 ames Murra5* ruce oling* <l rippo* en ;ulver* err5Doffmann* Matt ;ramer and ean elanger. ou ma5 share this file in its unaltered form or print out copiesfor 5our on personal use.

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Megasquirt-2 Setting 6p 2!7uic8Start uide - expanded

2: QuicStart !uide - e)pandedThis section expands on the &are &ones quic8start guide ith more detail in each step.

2.1 (u& or uild &our Me'asquirt)efore 5ou can &egin 5our installation* 5ou need to have purchased 5our Megasquirt/Microsquirt.

,n the case of a 8it 5ou need to assem&le it. it assem&l5 is covered in the hardare guide for 5our product.

2.2 Select and assemle &our *uel and i'nition s&stems

Befer to the hardare guide for 5our product for fuel and ignition s5stem details.

Ensure that 5ou have resistor t5pe spar8 plugs. on-resistor plugs are not suita&le for use ith E9, s5stems.

2.3 Setu% &our vehicle wirin' harness +loom, ensurin' it is *used.

iring is covered in the hardare guide for 5our product.

<n5 unused sensor inputs )M<(* ;CT* M<T* T(S* @2 should &e connected to sensor ground to prevent thesignal FfloatingF.

2.4 Connect M-P hose to *ull vacuum source.

Most installs use the Speed-+ensit5 method for fuel calculation and require a M<( sensor. Ensure that theM<( sensor hose is connected to a source of full inta8e vacuum. i.e. full5 donstream of the throttle plate.Engines ith individual throttle &odies ill ant to tee into each throttle runner to gain an averaged signal.

,n cases here M<9 or T(S )<lpha- are used exclusivel5 for load measurement* then the M<( sensorconnection can &e omitted.

2." nstall /unerStudio and Me'alo'viewer ou E;6 is tuned using TunerStudio on a indos* Mac or Cinux computer.

,f 5our E;6 came ith an install ;+ or pen drive* run it no to install the softare.

The latest versions can &e donloaded from .msextra.com/donloads

9or Cinux* 5our current user needs to &e a mem&er of the FdialoutF* Floc8F and/or FuucpF groups in order toaccess 5our comms port.

2.0 Power u% &our EC

o it is time to poer up the E;6. Either in the vehicle or on the &ench* appl5 a fused 02" suppl5 to poer

and ground inputs. Befer to the hardare guide for 5our product for iring details.

2.# et the serial comms set u%

MS2 and Microsquirt use BS232 serial communications for tuning ith a standard +? female connector.Some older or 1industrial1 t5pe laptops ill include a true serial port* most computers onl5 have 6S and a6S-serial adapter ill &e required. 9T+, &ased ca&les are recommended.

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http://www.msextra.com/downloads





MS2 serial port.

Microsquirt serial ca&le.

Standard +? male connector on computer.

Standard +?-+? straight through serial ca&le.

;omputer 6S soc8et

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T5pical 6S-serial adapter

efore inserting a 6S-serial adapter* follo the manufacturersF instructions for driver configuration.

)indos onl5 Daving found 5our true serial port or plugged in 5our 6S-serial adapter* it is desira&le toopening up +evice Manager and identif5 the ;@M port num&er. The method to open +evice Managerchanges ith each indos version* so ill not &e documented here.

The a&ove is a screenshot from indos N(* shoing the +evice Manager and the su&-panes shoing thatthis 6S-serial adapter has &een assigned ;@M0 - remem&er that num&er:

,f 5ou +@ @T see 1(orts1 listed in the devices then 5ou do not have an5 ports setup. This ould usuall5indicate either 5ou forgot to plug in 5our 6S-serial ca&le or there is a driver pro&lem. 6suall5 the &estsolution to the driver pro&lem is to unplug the ca&le* uninstall the driver and then re-install the driver.

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<lternative )indos onl5 - donload and run portchec8.exe from .msextra.com/donloads

Ta8e a note of the ;@M port num&er listed a&ove. ,n this case it as ;@M0.

Should 5ou encounter pro&lems getting 5our serial connection or8ing* refer to the fault finding section.

2. /urn o** Hide e5tensions *or 6nown *iles t&%es +7indows 8nl&,

indos has a feature to hide part of the filename. ,t is strongl5 advised that this is disa&led to preventconfusion.

o to 9older @ptions )6se Search to find it if required.

Ensure that 1Dide extensions for 8non files t5pes1 is not tic8ed.

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2.9 nstall the *irmware i* required

(lugFnFpla5 E;6s ill usuall5 &e supplied ith the firmare loaded and a tune read5 for 5our engine. ,n thesecase there is no reason to load ne firmare and 5ou can s8ip to step 2.?.

9or most other situations it is desira&le to load in the current firmare version to the E;6 &efore 5ou &egin

tuning.

The latest versions can &e donloaded from .msextra.com/donloads .

i. ;reate a folder/director5 for MS2. e.g. ;!OMS2 .

)6se 1M5 ;omputer1 or 1indos Explorer1* open Cocal +is8 ;! and ;reate e 9older* name it MS2 .

ii. +onload the firmare .Lip file from the donloads page. Bight clic8 and Save Target <s into the ;!OMS2folder.

iii. 6se M5 ;omputer / indos Explorer and &rose to this folder )e.g. ;!OMS2.

iv. Bight clic8 on the file 5ou saved and choose Extract <ll.

v. The defaults are @* and Aust clic8 next. )ote that indos adds a second level of director5.

vi. ou should no find the files have &een extracted. @pen up the folders until 5ou see this!

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vii. 6sers loading firmare for the first time can s8ip to viii.

6pgrade users should ensure that 5ou have used Save Tune <s to save 5our existing tune settings.

viii. Exit 5our tuning softare and ensure nothing is using the serial port.

ix. +ou&le clic8 on ms2loaderPin32.exe ),f 5ou get a securit5 arning* clic8 Bun

The loader is text &ased. <nser all of the questions &5 pressing the required 8e5 on 5our 8e5&oard.

e careful on the MS2/Microsquirt choice!

• MS2 Q E;6s ith an MS2 daughtercard.

• Microsquirt Q &lac8 plastic cased E;6.

• Microsquirt module Q +,(( or other E;6s that use the Microsquirt module.

• MS((2 Q +,autotune MS((2 onl5.

Example!

MegaSquirt-2 9irmare Coader 3.22 2#02-#%-#2.Bemove the fuse poering 5our ignition coils.)Spar8 outputs ma5 &e undefined until 5ou re-load 5our settings.(ress enter to continue...

.Ensure that 5our Megasquirt/Microsquirt/E;6 is-connected to 5our computer-has fused 02" poer connected.(ress enter to continue....Ensure that no tuning softare is running.e sure to 7uit the softare* not Aust minimise it..(ress enter to continue....

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+e&ug message Cevel!0! ormal2! More detail3! R serial comms4! R the s0? file as parsed

Selection )default! 0!.+o 5ou ant to scan 5our serial ports automaticall5G )5/n default 5.;@M0 MS2/Extra detected.+o 5ou ant to use ;@M0 )5/n default Q 5...9ound firmare files ! ms2PextraPus.s0? ! ms2Pextra.s0?.0! Megasquirt 2.

2! Microsquirt* Microsquirt module* +,((* MS((2...9ile to upload )0* 2* filename* defaultQ ms2Pextra.s0?! 0.(reserve sensor cali&rations )onl5 for MS2/Extra )5/n* default! 5G.QQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQSettings selected!Serial port! ;@M0S0? 9ile! ms2Pextra.s0?+e&ug level! 0umperless reflash ena&led

(reserving sensors cali&rationsQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQ(ress enter to continue...Sending Aumperless flash command<ttempting a8eup...9etching ! sensor cali&rationsErasing main flash:Erased.Sending firmare to controller...QQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQU0##.#HSending ! sensor cali&rationsrote 0#$#$2 &5tesVVV Settings not preserved. (lease re-load 5our MS7 / tuning settings VVV

(ress enter to continue....

,f this ta8es longer than a minute then 5ou li8el5 need to adAust the port settings of 5our 6S-serial adapter toreduce the latenc5 setting.

The first time 5ou install firmare on an MS2 it might &e necessar5 to use the &oot Aumper. @n a Microsquirtthe equivalent is to ground the @@TC@<+ ire.

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MS2 in normal condition ithout &oot Aumper.

,nstalling the &oot Aumper.

MS2 ith &oot Aumper in place.

2.1! et &our tunin' com%uter to tal6 to the EC

i. Start TunerStudio

ii. ;reate a ne proAect.

)More details on this step can &e found in the TunerStudio Beference manual in section 2.0

9rom the Start Screen select 9ile e (roAect

or from the Main Screen select 9ile (roAect e (roAect.

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,n the (roAect ame &ox 5ou can give the proAect a meaningful name if ish.

+ou&le chec8 that 5our Megasquirt is poered up and connected to 5our computer &5 serial.

iii. ;lic8 on ,etect

hen 5ou clic8 the J+etectK &utton a J+etect +eviceK screen ill appear and TunerStudio ill attempt to find5our Megasquirt and its firmare version. ,f successful it ill list 5our Megasquirt* firmare version and &audrate. ;hec8 to see that these appear to match 5our Megasquirt and then clic8 J<cceptK to continue. ,f theJ+etect +eviceK screen reports Jo controller foundK chec8 the connection &eteen 5our computer and 5ourMegasquirt and ensure that 5our Megasquirt has poer and tr5 again. ,f this still does not resolve thepro&lem move on to the J@ther / roseK method descri&ed &elo to set the firmare up manuall5.

,f 5our Megasquirt is identified correctl5* clic8ing J<cceptK should load the necessar5 firmare version. ;lic8ext and 5ou can no move on to step v.

,f 5our Megasquirt is identified correctl5 &ut clic8ing J<cceptK displa5s a message that reports JTunerStudiodoes not have a configuration to support the found hardareK then it is li8el5 either that 5ou are running anolder version of TunerStudio* or 5ou are running a &eta version of the firmare. ,f 5ou are running an olderversion of TunerStudio 5ou are strongl5 advised to update to the latest version. ,f 5ou are using a &etaversion of the firmare 5ou ill need to use the J@ther / roseK method descri&ed &elo to set up 5ourfirmare manuall5.

iv. t&er /ro(se

This method is recommended onl5 if TunerStudio is not a&le to detect 5our Megasquirt* or if 5ou are using a&eta version of the firmare.

The firmare on 5our Megasquirt ma5 have &een provided on a dis8 or donloaded as a .Lip file from the .msextra.com e&site. ,f 5ou have donloaded 5our firmare and havenFt done so alread5 extract thecontents of the .Lip file to a director5 of 5our choice.

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;lic8ing in the &ox next to J@ther / roseK opens a screen hich lets 5ou &rose to 5our firmare folder.9rom here 5ou should &e a&le to select the .ini file that 5ou ant to use. ,t is essential that 5ou use the .ini filethat is appropriate to 5our Megasquirt. There are four .ini files to choose from!

0. megasquirt2.ini W used for MS2.

2. microsquirt.ini W used for Microsquirt.3. mspnp2.ini W used for the +,autotune MS((2.

4. microsquirt-module.ini W used for the generic Microsquirt Module. ),f 5ou have purchased aproprietar5 Megasquirt-2 product &ased on the Microsquirt Module it is orth contacting themanufacturer to confirm hich firmare/ini version 5ou should use.

Select the file that is appropriate to 5our Megasquirt and then clic8 ext.

v. (roAect Settings

The settings availa&le on this list ma5 var5 &ased on 5our firmare. "erif5 that hat the5 are configured tomatch 5our set up. ,f 5ou are unsure* the default values are li8el5 to or8 ell. These settings can &echanged after 5our proAect has &een created.

vi. ;omms parameters

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enerall5 these can &e left alone. ;lic8 ext.

vii. +ash

;lic8 9inish.

The standard dash should displa5.

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2.1!.1 /unerStudio asics

e sure to read Section 0.$ in the TunerStudio Beference uide - this covers the user interface in detail.

To items are orthhile repeating here. Throughout the softare 5ou ill find Tooltips - clic8ing on the GU ill &ring up explanator5 text.

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@n most settings screens* 5ou ill also find a Delp menu - clic8 on this ill open up the TunerStudioBeference uide at the appropriate page so 5ou can read a&out all of the settings on this particular screen.)ou ma5 need to &e connected to the internet the first time 5ou use this feature* so the (+9 can &edonloaded.

2.1!.2 :irmware; /unerStudio; tune *iles +MS<, $ what=s all that>

The Megasquirt E;6 is a self contained computer hich runs a program to control 5our engine. Thisem&edded computer program is called the firmare. ;hanging firmare versions can give 5ou ne enginecontrol features. hen 5ou 1load firmare1 5ou are erasing the program from the chip and installing a freshversion. This process also ipes out 5our tune* so &e sure to use Save une As to save a cop5 of it first:

our tuning computer runs another program* called TunerStudio* that allos 5ou to tune 5our Megasquirt. esure to understand that TunerStudio is not running the engine: ;hanging TunerStudio version ma5 give 5oune tuning or displa5 features* it does not change hat can or cannot &e controlled on the engine. T5picall5* Aust use the latest TunerStudio version* thereFs no reason not to.

The tune file )MS7 file is a cop5 of 5our engineFs tune* saved onto 5our tuning computer. T5picall5 5ou canload in tunes that ere saved from older versions of Megasquirt firmare. The file format is designed to alloconversion of the data and a relativel5 smooth transition.

2.1!.3 Version numers

The various hardare and softare components ithin a Megasquirt s5stem have their on versionnum&ers* it is useful to have an understanding of hat the5 are so 5ou can get support for the currentproduct.

2.1!.3.1 Mainoard version

The main&oard versions "2.2* "3.#* "3.$% are covered in section 0.4.

2.1!.3.2 :irmware Version

This is the most critical version num&er. The firmare )e.g. megasquirt2.s0? is the computer program thatruns inside 5our Megasquirt and actuall5 controls the engine.

<lso supplied ith the firmare is the 1ini1 file )e.g. megasquirt2.ini hich defines all of the tuningparameters and tuning menus for the tuning softare.

,t is important that 5ou use the 1ini1 file that matches 5our firmare. ormall5* TunerStudio ill automaticall5detect and figure this out. ,f it doesnFt have the correct file in its local li&rar5* it ill attempt to donload it overthe internet. ,n unusual cases here this doesnFt or8 )e.g. development versions of firmare* 5ou can1&rose1 and point TunerStudio to the correct matching file.

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The title-&ar in TunerStudio shos &oth the TunerStudio version and the firmare version.

The 9irmare variant must match 5our particular hardare!

• MS2 Q MS2 card in traditional Megasquirt E;6

• uS Q ;ased Microsquirt - metal case "0* "2 or plastic cased "3

• uSM Q Microsquirt module and E;6s &ased on the module.

• (( Q +,<utotune MS((2

ote that there is also a 1serial format1 that is used internall5 &eteen the firmare and TunerStudio* this

loo8s similar to 1MS2Extra comms ....1 t&is is not t&e fir#(are *ersion and is generall5 not useful - use thefirmare version num&er from the TunerStudio title &ar.

2.1!.3.3 /unerStudio Version

<t time of riting* the current TunerStudio )TS version is 2.=.0?. Most of the tuning user interface )menusetc. are in fact determined &5 the firmare version. The TunerStudio version ma5 impact the use of tuningfeatures such as auto-tune or the dash&oard displa5s.

2.1!.3.4 Me'a?o'Viewer Version

<t time of riting* the current MegaCog"ieer )MC" version is 4.#.0>. This ill onl5 impact the vieing ofdatalogs* it does not alter direct tuning or engine operation.

2.1!.3." 8%eratin' s&stem version

e.g. indos N(* indos %* indos %* Mac @S N* 6&untu Cinux. Each operating s5stem has its on a5to find the version num&er.

2.11 Setu% sensor calirations to match hardware

o that the tuning softare and E;6 are communicating* the next step is to start cali&rating the sensorinputs.

These steps are covered in greater detail in the TunerStudio reference manual in section =.

2.11.1 Calirate /PS

The ;ali&rate T(S option allos 5ou to cali&rate 5our throttle position sensor. ;lic8ing ;ali&rate T(S illdispla5 the ;ali&rate Throttle (osition Sensor as shon &elo!

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To cali&rate the throttle position sensor do the folloing!

0. Ensure that 5our Megasquirt is connected and the engine is not running )i.e.* @E@.

2. Ensure that the throttle is closed'

3. ;lic8 the Jet ;urrentK &utton to the right of J;losed throttle <+; countK'

4. 9ull5 open the throttle'

$. ;lic8 the Jet ;urrentK &utton to the right of J9ull throttle <+; countK'

=. ;lic8 <ccept and 5our throttle sensor ill &e cali&rated.

2.11.2 Calirate M-P@(aro

The ;ali&rate M<( / aro option allos 5ou to cali&rate 5our M<( )Manifold <&solute (ressure andarometric (ressure sensors.

;lic8ing Tools ;ali&rate M<( / aro ill displa5 the ;ali&rate M<(/aro screen as shon &elo!

The ;ommon M<( Sensors gives a list of the commonl5 used M<( Sensors. ,f 5ou are using one of thesesensors select it from the drop don list* otherise select J;ustomK and enter the required num&ers.

Megasquirt 8its are usuall5 supplied ith a M(N42$#<( sensor.

Bepeat for the aro sensor settings.

2.11.3 nloc6 calirations

The cali&ration settings for Thermistor Ta&les* <9B Ta&les and M<9 Ta&les can &e loc8ed or unloc8ed to

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prevent them from &eing changed accidentall5.

;lic8ing Tools 6n/Coc8 cali&rations ill displa5 the 6n/Coc8 cali&rations screen as shon &elo!

Select 6nloc8ed and then ;lose.

Ensure that the cali&rations are re-loc8ed once 5ou have made 5our cali&rations.

2.11.4 Calirate C?/ and M-/ sensor

Megasquirt E;6s are supplied loaded ith the correct cali&rations for M temperature sensors. ou onl5

need to go through this cali&ration process if 5ou are using different sensors.

< process for determining the cali&ration num&ers is shon in the Dardare guide section 3.4.

Sensor $a"%e

Select hether 5ou are using a J;oolant Temperature SensorK or an J<ir Temperature SensorK.

$a"%e Input So%ution

This value ill normall5 &e set to J3 (oint Therm eneratorK.

Co##on Sensor a%ues

9rom this option 5ou can select 5our sensor t5pe. ou can select from a predefined list of common sensorsfrom the drop don list* or leave this option unselected if 5ou are using custom settings specific to an

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unlisted sensor.

/ias Resistor a%ue 1&#s

This is 24?# ohms unless 5ou or 5our vendor have changed the resistors inside the Megasquirt.

$e#perature Settings 13C or 34

<gain* if 5ou have selected one of the common sensors these values should &e set for 5ou. ,f 5ou are usinga custom sensor enter the three measured temperature and resistance value pairs.

5rite to Contro%%er

@nce 5ou have completed the settings in this screen clic8 the Jrite to controllerK &utton to &urn thesesettings to 5our Megasquirt.

Bepeat for &oth sensors if required.

2.11." Calirate -:R tale +82 sensor,

;lic8ing Tools ;ali&rate <9B Ta&le ill displa5 the ;ali&rate <9B Ta&le screen as shon &elo!

9rom this screen 5ou can set the <9B )air fuel ratio cali&ration if needed. The options for these settings aredescri&ed &elo!

E! Sensor

This option allos 5ou to select an exhaust gas ox5gen sensor. ou can either select from the predefined

list* select J;ustom Cinear K )ide&and or select J;ustom ,nc 9ileK.

o%ts 64R a%ues

,f 5ou have selected an E@ sensor from the predefined list these values ill &e set for 5ou. ,f 5ou have

selected J;ustom Cinear K then 5ou ill need to enter the voltage/<9B pairs from 5our sensor orcontroller manual.

5rite to Contro%%er

@nce 5ou have completed the settings in this screen clic8 the Jrite to controllerK &utton to &urn these

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settings to 5our MS2.

2.11.0 ?oc6 calirations

@pen Tools 6n/Coc8 cali&rations* select Coc8ed and then ;lose.

2.12 Chec6 all sensor in%uts are readin' sensil& in /unerStudio.

o that 5our have communication and have the sensor inputs cali&rated* it is time to chec8 that the sensorinputs ma8e sense.

+uring these steps 5ou ma5 need to change a gauge on the dash&oard ithin TunerStudio. To change anexisting gauge* right-clic8 on it and then select an alternate gauge from the popup menu. ou ill find therelevant gauges on 1Sensor inputs 01.

2.12.1 M-P sensor chec6

Ensure that the gauge 1Engine M<(1 is displa5ed.

,f 5ou are near sea-level a value close to 0##8(a should &e displa5ed. <t high elevations* expect to see areading closer to >#8(a. ote! These num&ers are ith the engine not running.

2.12.2 /PS chec6

Ensure that the gauge 1Throttle (osition1 is displa5ed.

The gauge should read #H hen the throttle is closed* smoothl5 seeping to 0##H hen the throttle is fullopen.

2.12.3 C?/ sensor chec6

Ensure that the gauge 1;oolant Temp1 is displa5ed.

ithin a fe degrees of the outside temperature is fine. ,f the sensor is removed from the engine 5ou canheat it up ith a t5pical hair drier and chec8 that the readout changes.

2.12.4 M-/ sensor chec6

Ensure that the gauge 1Manifold <ir Temp1 is displa5ed.

ithin a fe degrees of the outside temperature is fine. ,f the sensor is removed from the engine 5ou canheat it up ith a t5pical hair drier and chec8 that the readout changes.

2.12." 82 sensor chec6

The @2 sensor ill not read an5thing useful ithout the engine running.

2.12.0 M-: sensor chec6 Ensure that the gauge 1Mass <ir 9lo1 is displa5ed.

The M<9 sensor ill read Lero ith the engine not running* a leaf &loer or similar could &e used to simulateair-flo to chec8 that it is reading.

2.12.# (atter& volta'e chec6

Ensure that the gauge 1atter5 "oltage1 is displa5ed.

This should displa5 02-03".

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2.13 Set the ase settin's

The first rule of tuning is that 5ou do not ant to tune from a &lan8 file. ou can either connect to theMegasquirt and automaticall5 retrieve the tune on it or open an existing tune file* &ut stop if 5ou see thismessage!

This means that 5ou have no tune loaded. This is @ if 5ou are Aust having a loo8* &ut do not tr5 to start a

tune li8e this. TunerStudio ill default to a ta&le full of Leroed out values - or in some cases* the num&ers ill&e set to their loest possi&le value. ,tIs not orth chasing don all the nonsense values to turn this J&lan8fileK into a real tune. Start ith either the tune in the E;6 or one of the sample tunes provided in the softarepac8age.

e recommend that 5ou do not have the ignition coils hoo8ed up hile doing a &asic setup on the

Megasquirt. +uring the setup stage* 5ou ill define hat t5pe of ignition hardare that 5ou are using* &ut ifthe ignition 5ou have doesnIt or8 ith the default settings* 5ou ma5 overheat 5our ignition module anddamage it &efore 5ou are done ith 5our setup.

The folloing sections s8im through some of the required setting screens - &e sure to refer to theTunerStudio Beference Manual hich gives an expanded vie of each and ever5 setting.

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2.13.1 Control -l'orithm choice

There are a num&er of different methods to estimate the airflo into an engine. These depend on theavaila&le sensors and their accurac5 at predicting flo.

se S%eed$densit& unless &ou have a 'ood reason to choose otherwise.

<t the most &asic level!

• Speed +ensit5 uses the M<( )Manifold <&solute (ressure sensor to determine load. ,n this case*

the vertical axis of an5 fuel ta&le loo8ups is in 8ilopascals )8(a. The maximum value reported &5 theM<( sensor )in non-tur&o applications ill &e the same as the &arometric pressure.

Belativel5 eas5 to configure* or8s on &oosted engines and familiar to most tuners.

• <lpha- uses the T(S )throttle

;an &e a poor estimator of airflo. 6seful is a M<( signal is unavaila&le or unrelia&le.

e sure to cali&rate the throttle range using Tools-;ali&rate T(S &efore using this setting.

• M<9 uses an actual mass air-flo sensor and related calculations to directl5 determine the amount

of fuel to inAect. ,n this mode* the "E ta&le is not usuall5 used to determine the amount of fuel toinAect.

• ,T uses a com&ination of M<( and T(S

This mode as created specificall5 for naturall5 aspirated engines running ith independent throttle&odies. ,t com&ines alpha-n )at high engine loads ith speed densit5 )at lo engine loads* usingthe load calculation that ma8es the most sense at each B(M. 9or example* most ,T set-ups do nothave good vacuum at idle or lo B(M* and slightl5 touching the throttle ma8es them lose allvacuum* &ut at higher B(M start to respond more li8e a traditional single throttle &od5 engine. Thismode allos the use of speed densit5 set-ups at lo engine loads and sitches to alpha-n at highloads* ith an adAusta&le sitchpoint curve over B(M.

• H&aro uses a com&ination of M<( and a &arometer reading.

This setting is similar to the Speed +ensit5 setting in that the M<( sensor is used to determine load.Doever* instead of directl5 using the manifold pressure* the manifold pressure is divided &5&arometric pressure to give a percentage of &arometric pressure. This setting can &e useful for those ho regularl5 drive at high altitudes. ,t ensures that regardless of &arometric pressure* all ta&leloo8ups operate over #-0##H. 9or example* if &arometric pressure is >#8(a* and the engine isoperating at $#8(a* the actual value used for ta&le loo8ups is $#8(a/>#8(a or =2.$H.

<ll have pros and cons. Badical engines ma5 need to use a com&ination of algorithms. Man5 engines ill getgood results ith Speed +ensit5 or M<9.

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2.13.2 En'ine and Sequential settin's

The most critical settings are on the left. ;omplete the ;ontrol <lgorithm through to ,nAector siLe settings. ,funsure* leave alone:

Then clic8 on the 1Bequired 9uel1 &utton to calculate the 1Beq9uel1 num&er.

2.13.3 nAector dead$time

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,t is important to select the correct dead-time setting for 5our inAectors and hardare.

T5pical dead-times at 03.2 volts!

• Digh impedance inAectors - dead-time Q #.>-0.# ms

• Co impedance inAectors ith resistors - dead-time Q #.>-#.? ms

• Co impedance inAectors ith (M )MS2 onl5 - dead-time Q #.=-#.> ms

• Co impedance inAectors ith external pea8/hold - dead-time Q #.=-#.> ms

2.13.4 'nition setu%

iring and configuring 5our ignition setup covers the tach input )ho Megasquirt gets an B(M signal andho the ignition coil or coils are controlled.

The exact details depend on hich Megasquirt-2 product 5ou have* so this section is covered in thehardare guide for 5our product.

Each setting needs to &e revieed and set appropriatel5* hoever* if unsure* leave alone:

2.13." dle Valve

The specific iring for 5our idle valve is covered in the hardare guide for 5our product.

+uring initial startup it is strongl5 advised that the open-loop )armup algorithm is selected. +o not tr5 touse closed-loop until the engine can maintain a stead5 idle speed on its on.

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Stepper idle users need to configure the num&er of homing steps - this is covered in the section on idle valvetesting - 2.04.4.0. 9or no* set the homing steps to 2$# and ensure that all values in the armup curve areless than 0>#.

9or &oth (M idle and stepper idle* a larger dut5 or steps num&er means more air i.e. higher idle. The armup curve ill start at larger num&ers on a cold engine and smaller num&ers on a hot engine.

2.13.0 8ther in%uts@out%uts

+uring the initial startup it is advised that other* optional inputs and outputs are left disa&led )shift lights* fancontrol* launch control* nitrous control etc. - so long as the5 are not required for engine operation.

2.13.# au'e@Settin' ?imits5 default* the B(M settings ithin TunerStudio are set to displa5 an B(M range suita&le for most carengines. ,f 5our engine has a higher B(M range* &e sure to adAust the asic/Coad Settings - auge andSettings Cimits to set the limits that suit 5our install.

;hanging these settings does not alter the &ehavior of 5our engine in an5 a5* the5 @C change the limits hich can &e displa5ed on the screen and set the threshold limits for 5our tune.

@nce these settings have &een changed it is necessar5 to close and restart TunerStudio for thechanges to &e reflected in the gauge cluster.

2.13. Power C&cle Required hen 5ou change some settings or ena&le a ne feature* this message ill pop up.

T5picall5* 5ou should complete the settings changes on that page and urn. Then turn the poer off )8e5 off*pause* then poer on )8e5 on.

,f 5ou are ma8ing multiple changes during intitial setup* 5ou can ait until 5ou have made all of the changes&efore c5cling the poer.

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Ma8e sure that 5ou clear this arning message &efore tr5ing to start the engine.

2.13.9 Con*i'uration Error

+uring the configuration of 5our Megasquirt-2 5ou might ma8e a mista8e and set an impossi&le com&inationof settings. ;ommon mista8es are selecting the same output to to different features or tr5ing to ena&le anignition output t5pe that is not possi&le ith 5our tach input.

ou ill see this message popup hen 5ou turn on the Megasquirt-2

and this message ill sho across the auge ;luster.

The other tell-tale signs are &ogus high B(M is reported

and a config error indicator lit up

The final arning message is the fuel pump - at poer-on the pump ill run three times.

+o( to fi) it7

0. Bead the message - it tells 5ou hat to do.

2. ,f 5ou have a pin conflict* ta8e a loo8 at asic/Coad Settings - 9eature Cist Shoing ,/@ (ins

5ou should &e a&le to spot here 5ou have set to features to use the same connection.

3. ;hange the setting that 5ou are &eing arned a&out.

4. ,f 5ou are reall5 stuc8* then load in an old tune file )MS7 that 5ou previousl5 saved using 1Save Tune <s1.

This message has @TD, to do ith iring or an5 internal fault.

,t is solel5 a setting mista8e that 5ou have made.

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dut5* a&ove that the valve operates as expected here more dut5 gives more airflo. elo this specificpoint is a fail-safe mode that allos airflo even if there is no control signal. This is readil5 o&served duringtest mode.

There are three control &uttons!

• Ena"%e $est - +o#e Position - for stepper idle valves* this moves the valve through the num&er ofhoming steps &ac8 to the home position. ),f it doesnFt get all the a5 &ac8 to the stop* increase thenum&er of homing steps. The valve ill move to the run position shortl5 afterards.

• Ena"%e $est - Run Position - ena&le test mode here the steps or dut5 setting controls the valve

position• Stop $esting - disa&le test mode and allo normal idle control to operate.

Dere is an example of a fixture used to measure stepper operation on the &ench* although ver5 fe users illneed one of these.

2.14.4.1 sin' the test mode to determine ste%%er homin' ste%s

,n the initial setup* rough values ere given for the homing steps and maximum num&er of steps to use inthe curves. @nce the engine ill start and run and after 5ou have performed some initial tuning* 5ou canreturn here to validate these settings. The engine ma5 reach 3###B(M or so ith a ide open idle valve* sodo not attempt this procedure until 5ou are read5 to do that. This procedure assumes that 5ou are homing tothe closed direction.

• Start the engine and run up to temperature.

• @pen ;< us/Testmodes @utput test mode - ,dle valve.

• Set F,dle "alve Doming StepsF to 3##.

• ;lic8 FEna&le Test - Dome (ositionF )ou ma5 need to open the throttle to prevent a stall.

• The idle valve should move to the full5 closed position and the revs ill drop.

• Set F,dle "alve StepF to 0##.

• ;lic8 FEna&le Test - Bun (ositionF

• The idle valve ill open somehat and the revs ill increase* note the revs.

• Set F,dle "alve StepF to sa5 0$#.

• The idle valve ill open some more and the revs ill increase* note the revs.

• ;ontinue to increase the steps num&er until the revs stop increasing.

• Be-home the valve and chec8 0# steps either side.

The steps num&er 5ou have found is the num&er of steps from full5 closed to full5 open. Sa5 it as 0>$. The1homing steps1 setting on the idle control page should &e set around 0# steps higher than this - to ensure

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that the idle valve ala5s reaches the closed stop full5 at 8e5-on. Ensure that 5our armup curve or closed-loop idle settings are a maximum of around 0# steps less than this num&er.

,f 5ou mista8enl5 tr5 to open the valve more steps than full open* the overrun clutch in the stepper idle valve ill prevent damage as the pintle hits the full open stop* &ut the E;6 ill lose trac8 of here the valve is.This ould most li8el5 result in random idle speeds depending on hat temperature 5ou first started the

engine.

2.1" Chec6 *or cran6@cam tach$in si'nals

efore cran8ing the engine!

• pull the fuses for fuel pump* inAectors and coils

• chec8 that the engine has sufficient oil of the correct grade

• chec8 that an5 trans cooler lines are connected.

• chec8 that the transmission is in neutral

• chec8 par8ing &ra8e is firml5 latched on

5e do not (ant t&e engine to start yet.

e5-on the engine* then open up the 1+iagnostics Y Digh Speed Coggers1 ta&* then select the 1;ompositeCogger1 from the dropdon and clic8 Start.

;ran8 the engine for 0#-2# seconds.

ou should see a pattern sho up loo8ing something li8e this!

This example includes a cam signal. ,f 5our install onl5 uses a cran8 signal then the green trace ill correctl5&e missing.

,f the turquoise 1cran81 signal is missing* 5ou have a pro&lem and need to fix it.

ext* repeat the process using the 1Tooth Cogger1

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The screenshot here shos a real =#-2 cran8 pattern at cran8ing speed* the 1missing tooth1 is the single long&ar in the middle. The c5clic pattern is due to the compression effect as the spar8 plugs ere in.

Dere is an example of an incorrect pattern - the missing tooth shos as to long &ars instead of one. This onFt or8. Sap the R/- on the sensor or change the 1,gnition ,nput ;apture1 from Bising to 9alling or vice-versa.

These are Aust a fe examples or the patterns 5ou might see. The Megasquirt product range supports a largenum&er of different trigger input patterns hich all loo8 different. ;ount the num&er of &ars )including the longone in the repeating pattern on the tooth logger and see if it loo8s reasona&le. 3=-0 heels ill have 3$&ars total* =#-2 ill have $> total.

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2.10 Chec6 *or RPM in%ut

@nce 5ou have completed the previous step and have the 1cran81 and 1cam1 )if used inputs shoingsomething sensi&le 5ou can chec8 for B(M.

Sitch &ac8 to the 1auge ;luster1 ta& in TunerStudio.

@nce again* &efore cran8ing the engine* &e sure to pull the fuses for fuel pump* inAectors and coils.

;ran8 the engine and atch the 1Engine Speed1 gauge and indicators section.

ou need to see sensi&le and sta&le B(M and the green 1B(M S5nced1 indicator. Expect to see B(Ms of2##-=##B(M depending on the engine and outside temperature.

,f the B(Ms are &ouncing up and don )e.g. 4##* #* 4## or the B(M S5nced indicator is flashing &eteengreen and red 5ou have a pro&lem. Befer to section $.2 for information a&out common causes for s5nc-losses.

,o not proceed any furt&er unti% you &a*e sta"%e RPM and RPM-sync.

2.1# Chec6 sensors durin' cran6in'

ith the B(M no reading @* it is orth chec8ing that sensors are still reading correctl5 during cran8ing.


;ran8 the engine and atch the 1;oolant Temp1 and 1Manifold <ir Temp1 gauges. The gauges should notchange during cran8ing. ,f the5 do change significantl5* 5ou almost certainl5 have a sensor ground iringfault. 9ix that &efore continuing.

+uring cran8ing the 1Engine M<(1 gauge should drop from around 0##8(a to sa5 >#8(a. This ill dependon the engine* altitude and throttle position. Some drop is required. ,f it doesnFt move* ma8e sure that thehose is connected from the sensor to the inta8e manifold. ,f 5ou arenFt using the M<( sensor )<lpha- orM<9 then 5ou can s8ip this.

2.1 Sam%le datalo'ith the B(M no reading @* it is orth chec8ing that sensors are still reading correctl5 during cran8ing.


Start a datalog )+atalogging - Start +atalogging

;ran8 the engine for a&out 0# seconds.

Stop the datalog )+atalogging - Stop

@pen the datalog to vie )+atalogging - "ie ith MegaCog"ieer

,n Megalogvieer* the field selectors are on the left* ensure that 5ou have M<(* T(S* B(M* ;CT* M<T* att"ena&led.

The log should start ith att" at a&out 02"* M<( at a&out 0##8(a* T(S around #H. ;CT* M<T shouldreflect outside temperature* B(M ill &e #.

<t the start of cran8ing 5ou ill see the att" drop to >-0#"* along ith a small drop in M<(. Then the B(Msshould register a reading. ;CT* M<T* T(S should not change.

@nce 5ou have had a loo8* 5ou can close MegaCog"ieer.

2.19 Chec6 the cran6in' timin' with *uel disaled

Daving confirmed that the coils or8 as expected and that e can get sta&le B(M it is time to chec8 the

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timing. ou ma5 need an assistant.

es* this step is reall5 needed - correct ti#ing is *ery i#portant.

),f 5ou feel li8e s8ipping this step* please as8 5ourself hether 5ou ould rather chec8 5our timing no orre&uild 5our &ro8en engine soon.

,f 5ou are running asted spar8 5ou need to ensure 5our stro&e is compati&le. 1+um&1 timing lights are fine'

some dial-&ac8 lights can &e a8ard. 6se a 12-stro8e1 setting for asted-spar8 or asted-;@( if 5ou havea dial-&ac8 light. ith a coil-on-plug pencil t5pe coil 5ou ill need to remove the coil from the engine andinstall a short length of regular spar8 plug ire from the ;@( to the spar8 plug* and possi&l5 ground the ;@(if it as &olted on. ;onnect 5our timing light over this temporar5 plug lead.

,f there are no timing mar8s on 5our engine* 5ou ill need to add some sort of mar8s and a pointer. ou needto mar8 here the pointer lines up ith the damper hen the engine is at T+;X0. ou can esta&lish T+; ith a piston stop and add timing mar8s ith either paint or timing tape.

@nce again* &efore cran8ing the engine* &e sure to pull the fuses for fuel pump and inAectors. Be-install thefuse for the coils.

Temporaril5 set the cran8ing advance ),gnition Settings - ,gnition @ptions / heel +ecoder - ;ran8ing<dvance to #.

;ran8 the engine and confirm that X0 timing is somehere close T+;.

),n 9uel @nl5 mode* Megasquirt isnFt controlling 5our timing* so 5ou ill need to adAust hatever is controllingit as required.

<dAust the Tooth X0 <ngle setting )if running Toothed heel or Trigger <ngle / @ffset )if running an5 otherspar8 mode &esides 9uel @nl5. ,f the timing is too far advanced* increase this num&er. ,f the timing isretarded* decrease this num&er. ,f adAustments of more than 0# degrees are required* ma8e the change* clic8urn* turn the 8e5 off and chec8 again. "er5 large changes donIt ta8e effect until 5ou turn the Megasquirt offand &ac8 on again.

@nce the timing lines up during cran8ing 5ou should return the ;ran8ing <dvance setting to its previous

value )e.g. 0# T+; and urn.+uring this step 5ou should also chec8 that the engine is developing oil pressure.

2.2! Start the en'ine and start tunin'

o that 5ouIve confirmed sensor inputs* coil and inAector outputs* have good B(M and cran8ing timing isclose 5ou are read5 to start the engine.

+ou&le chec8 the oil level and that the coolant s5stem is filled.

Beplace the fuses for fuel pump* inAectors and coils )since e removed them in previous tests. Ensure thatthe &atter5 is charged* spar8 plugs are fitted* plug leads are in place and all hoses are secure. erecommend starting a data log as ell. hile the engine ill usuall5 start if 5ouIve gone through all theprevious steps for setting up* sometimes 5ouIll need a couple more tea8s* and the data log can &e ver5

valua&le if it comes to that. o to the +ata Cogging menu and select Start Cogging. The log starts hen 5ouclic8 Save* and stops hen 5ou either close TunerStudio or go to the +ata Cogging menu and select Stop.

o* hit the starter* and hope the moment for the &ig pa5off has arrived.

,t is common to need to give the engine a little throttle to 8eep it alive on the first start. ,f all sounds ell* then8eep the engine running and arm it up. ;hec8 for oil pressure* coolant temperature etc. ,f an5thing sounds rong - stop and investigate.

$ae your ti#e9 ,f things arenIt or8ing out* then ta8e a &reather and come &ac8 another da5. ;ome to the .msextra.com forum and as8 for help. hen posting* please include full details of 5our install! engine

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t5pe* ma8e* model* ignition setup. The forum is glo&al and e might not &e familiar ith 5our engine* so Austquoting an engine code is not sufficient. +onIt use the forum to vent 5our frustration* 8eep it calm...

,f 5our engine does not start in spite of having a functioning fuel and ignition s5stem and timing that appearsto &e correct* here are several things e recommend chec8ing that commonl5 ill cause a no start condition.

•

,f 5ou are running full sequential fuel and / or coil on plug ignition* tr5 changing these settings tosemi-sequential fuel and asted-;@( ignition. This ill rule out the possi&ilit5 that the cam sensorhasnIt &een set up correctl5* and 5ouIre firing on the exhaust stro8e instead of the inta8e stro8e.These changes ill ma8e it fire on &oth* hich can &e ver5 useful for de&ugging startup pro&lems.

• ,t ma5 &e refusing to start &ecause the fuel isnIt quite right. ,f the engine does not go a&ove start-up

cran8ing B(M* tr5 adAusting the cran8ing pulse idth )the ;ran8ing (ulse menu under Startup /,dle. ,f the engine catches &ut dies immediatel5* tr5 adAusting the afterstart enrichment )<SE(ercentage under Startup / ,dle. oth of these are temperature dependent* so &e sure 5ouIreadAusting them at 5our actual coolant temperature. ThereIs a couple rules of thum& 5ou can usehere!

• Start at hat 5ou thin8 ma5 &e a lean value* then or8 5our a5 up in small increments.

•

(ull a spar8 plug after a failed start and chec8 the electrode. ,f itIs et ith fuel* decrease theamount of fueling. ,f itIs dr5* increase it. <nd if the electrode is covered ith crud* 5ourpro&lem ma5 Aust &e that 5ou need ne spar8 plugs.

• ,f the engine responds &etter if 5ou give it a &it of throttle* 5ou pro&a&l5 have too much fuel )&ecause

the extra air helps get 5our air/fuel ratio closer to hat it should &e. So 5ou need less fueling.;onversel5* if giving it the throttle ma8es things orse* 5ou pro&a&l5 need more fuel.

• ;hec8 for various ph5sical pro&lems. Some examples ,Ive seen include coil pac8s or distri&utors

ith one or to spar8 plug ires run to the rong c5linders* a &ro8en 8e5a5 on the cran8shaftpulle5 causing the timing mar8s to &e =# degrees off* and even a Lip tie that got pinched in theinta8e manifold gas8et next to a coolant passage* hich nearl5 h5droloc8ed the motor.

2.21 Run en'ine u% to tem%erature

@nce 5ou have got the engine to start* 8eep it running and &ring it up to temperature. ,t is normal to need touse some throttle to 8eep it alive. Step 2.0> can &e performed during armup.

hile the engine is arming up* chec8 for oil and coolant lea8s.

,f possi&le* chec8 the exhaust temperatures on each c5linder. Expect to see a variation &eteen c5linders.+ifferences of up to 0>#9 )0##; are fairl5 normal. e5ond that 5ou need to investigate h5. There could &ean air lea8* a fault5 inAector* a damaged valve seat or other mechanical issues ith the engine. ,f c5lindersare ver5 cold* stop the engine and chec8 for a fouled plug.

(a5 attention to the engine! if something loo8s* sounds or smells rong - ST@(:

2.22 Settin' runnin' timin'

o that the engine is running* e can come &ac8 and ma8e the final timing adAustments. This step can &eperformed hile the engine is arming up.

Doo8 up 5our timing light and start 5our engine. ,n TunerStudio* on the ,gnition @ptions / heel +ecodermenu* set 9ixed timing to 19ixed Timing1 and clic8 urn.

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This loc8s the timing to the advance 5ou specif5 in the 1Timing for 9ixed <dvance1 &ox. ou do not need toalter 5our spar8 ta&le.

• Enter sa5 0$ degrees )or another angle that 5our engine ill idle easil5 at.

• 6sing 5our timing light* confirm that the timing on the cran8 matches the fixed advance at lo B(Ms

• ,f it does not* then adAust 5our toothX0 angle )trigger heel or trigger angle/offset )other spar8

modes.

• ,f the actual timing is more advanced than Megasquirt thin8s* then increase the trigger angle/offset. ,f

adAustments of more than 0# degrees are required* ma8e the change* clic8 urn* turn the 8e5 off*and restart the engine.

•

@nce 5our idle timing is matching up ith 5our fixed angle* increase the engine revs and confirm thatthe timing does not drift.

,f 5ou get a large timing advance ith increased rpms on a "B sensor distri&utor then it is li8el5 that 5ourignition input capture is &ac8ards.

9or a fe ignition configurations* it is also possi&le that 5our spar8 output setting is rong - hoever*exercise caution in changing this* as the rong setting can damage 5our coils or ignition module. Mostconfigurations should use 1oing Digh1 &ut this does depend on the product and coils.

,f the timing retards a little as rpms increase 5ou can ma8e a correction &5 adAusting the Spar8 DardareCatenc5 setting. The larger the num&er* the more compensation it ill appl5.

,o not proceed any furt&er (it& your insta%% if you cannot get sta"%e ti#ing. ote that Jsta&le timingK isa matter of degree - a small &loc8 ;hev5 ith an DE, distri&utor and a orn timing chain* for example* ma5

have 2 or more degrees of timing Aitter in normal operation. <nd man5 dial-&ac8 timing lights ill havepro&lems 8eeping up ith rapid changes in B(M. ut if 5ou are seeing the timing &ouncing around &5 0#degrees or more* stop and investigage hatIs rong.

hen finished* &e sure to turn off the 9ixed Timing and return to 6se Ta&le and clic8 urn.

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Megasquirt-2 Setting 6p 3!Tuning the engine

: $uning t&e engine

3.1 How it wor6s $ *uel

The amount of fuel inAected into the engine is controlled &5 the fuel pulseidth 1(1. This pulseidth iscalculated &5 the Megasquirt from a num&er of factors. ,t is important to understand hat these are to 8no hat settings* curves and ta&les need to &e tuned.

3.1.1 Cran6in' mode

hen the engine is in cran8ing mode )i.e. &efore it is has started and is &elo the 1;ran8ing B(M1 settingthere are a limited num&er of settings that influence the fuelling.

The primar5 setting is!

• ;ran8ing (ulse curve

Sensor inputs!

• B(M input

• Throttle (osition

• ;oolant Temperature

The B(M input is used to determine hether the engine is tr5ing to start and should &e in cran8ing mode.

The Throttle (osition onl5 ta8es effect at full throttle - this can &e used to disa&le fuel to clear a floodedengine. ,f the T(S is &ro8en or malfunctioning* it could ena&le flood-clear &5 accident and the engine ill notstart.

The ;oolant Temperature is used as a loo8up on the ;ran8ing (ulse curve to determine ho much fuel toinAect.

)< future revision ma5 also use the Beq9uel num&er* &ut that is not used at this time.

8ote t&at none of t&e ot&er fue% ta"%es and cur*es are used during craning.

3.1.2 Run mode

@nce the engine has fired and the B(Ms exceed the 1;ran8ing B(M1 setting* the run mode calculations areused. o all of the availa&le settings are used.

The primar5 settings are!

• Beq9uel

• "E ta&le

The secondar5 settings are!• <9B ta&le )onl5 ith ,ncorporate <9B

• <ccel enrichment

• "E Trim

• M<9 flo curve

• arm6p Enrichment curve

• <fterStart Enrichment curve

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Sensor inputs!

• B(M input

• M<( sensor

• M<9 sensor


• <ir Temperature


• 9lex fuel sensor

The exact ta&les and sensor inputs used varies depending on the selected fuel <lgorithm and are covered inthe appropriate tuning section.

@f particular note is the <9B ta&le. hen Fincorporate <9BF is off* the <9B ta&le is a reference ta&le onl5 andis not used for fuel calculations. hen Fincorporate <9BF is on* this ta&le is included in the fuel calculation.

The 9uel ;alculations Summar5 screen shos man5 of the factors that are used to arrive at the finalpulseidth.

More detail on the a5 the fuel calculations or8 internall5 ma5 &e found in <ppendix .

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3.2 How it wor6s $ i'nition

The final ignition timing )spar8 advance is calculated &5 the Megasquirt from a num&er of factors. ,t isimportant to understand hat these are to 8no hat settings* curves and ta&les need to &e tuned.

3.2.1 Cran6in' modehen the engine is in cran8ing mode i.e. &efore it is has started and is &elo the 1;ran8ing B(M1 setting.There is Aust one setting that influences the advance.

The primar5 setting is!

• ;ran8ing <dvance setting

Sensor input!

• B(M input

The B(M input is used to determine hether the engine is tr5ing to start and should &e in cran8ing mode.hen in cran8ing mode the 1;ran8ing advance1 setting onl5 is used.

8ote t&at none of t&e ot&er ignition ta"%es and cur*es are used during craning.

3.2.2 Run mode

@nce the engine has fired and the B(Ms exceed the 1;ran8ing B(M1 setting* the run mode calculations areused. o all of the availa&le settings are used.

The primar5 settings are!

• ,gnition ta&le

The secondar5 settings are!

• ;old <dvance

•

M<T Betard• Bev/launch limiter retards

• itrous retards

Sensor inputs!

• B(M input

• M<( sensor

• M<9 sensor


• <ir Temperature


• 9lex fuel sensor

• Caunch/nitrous sitch inputs

The exact ta&les and sensor inputs used varies depending on the selected fuel <lgorithm.

The Spar8 ;alculations Summar5 screen shos man5 of the factors that are used to arrive at the ignition

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)spar8 advance.

3.3 /ales and curves

The TunerStudio Beference uide section 0.$ gives an overvie of settings screens* curves and ta&les.

3.4 /unin' *uel

<s outlined in section 3.0* there are a num&er of curves and ta&les that are used to tune fuel. o e illcover them in more detail.

Bemem&er that all initial tuning should &e on a armed up engine. )Tune armup and <fterstart onl5 oncethe main tune is good.

The (rimar5 9uel Coad )<lgorithm determines ho fuelling or8s* these algorithms ill &e handled in theiron sections to 8eep the details clear. ou should have alread5 set this is section 2.02.0

The Engine Coad gauge shos the value of the selected load input.

3.4.1 /unin' *uel $ S%eed Bensit&

Speed +ensit5 uses a M<( )pressure sensor as the Coad input.

3.4.1.1 -:R tale +SB,

The <9B ta&le can &e used in different a5s.

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• ,f 5ou set J,ncorporate <9B TargetK under the eneral Settings menu to Jinclude <9Btarget*K it ill

scale the pulse idths &ased on the num&ers entered.

• ,t can &e used for closed loop @2 correction ith a ide&and @2 sensor.

• ,t can &e used purel5 as a reference ta&le for external tuning. ,n this case it is not used internall5 at

all.

o* letIs ta8e a loo8 at ho 5ou use this particular ta&le.

ouIll enter the <9B 5ou ant at each B(M and load point. Most sequential fire engines ill run &est at04.%!0 at idle. atch-fire engines ill li8el5 need to run richer. <t cruising B(M and lo load* 5ou can run04.%!0 or sometimes leaner depending on the engine. Most naturall5 aspirated engines tend to run &est at03.2 to 03.$ at full throttle* hile engines running forced induction ma5 need to run as rich as the mid 00Isunder &oost.

,f 5ou set J,ncorporate <9B TargetK under the eneral Settings menu to Jinclude <9Btarget*K this ta&le isused to scale the fueling. < ta&le entr5 of 04.%!0 ill mean no fuel scaling. um&ers less than that illincrease the fuel* and num&ers higher ill decrease the fuel. hen using this mode* 5ouIll tune 5our "E ta&leto hit 5our <9B targets* then adAusting the <9B target ta&le ill directl5 adAust the fuel to the desired <9Bnum&er.

efore having 5our engine d5no tuned - ma8e sure the d5no operator is clear a&out 5our selection for1,ncorporate <9B Target1 and hether the <9B ta&le is &eing used. @therise the operator ma5 aim for hison <9B target and ignore the ta&le causing later confusion.

3.4.1.2 VE tale +SB,

The "E ta&le is 5our primar5 tuning ta&le. <t its simplest* &igger num&ers equal more fuel.

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,n an5 mode that uses this ta&le* the num&ers in the "E ta&le are a percentage. The fueling equation ta8esthe &ase pulse idth from Bequired 9uel* scales it &5 the percentage in the "E ta&le* and then applies an5other corrections* enrichments* and the li8e* such as air densit5 correction and armup enrichment. ,f 5ouhave the tuning set to incorporate the <9B target* theoreticall5* the "E ta&le ill match the engineIs actualvolumetric efficienc5. +onIt &e alarmed if 5ou need to enter num&ers a&ove 0##* particularl5 in &oost. Themaximum num&er is 2$$.

e recommend first setting up an appropriate <9B ta&le* then adAust the num&ers in the "E ta&le )upardsto add fuel* donards to ta8e it aa5 until 5our actual air/fuel ratio hits the target ta&le.

efore starting to tune the "E Ta&le* it is recommended that 5ou turn the <cceleration Enrichment )<E off so5ou can see hats happening to the mixture as a direct result of the ta&le rather than having fuel added from<cel Enrichment. See the next section on ho to sitch this off. ou ma5 find that 5ouIll need to &e light onthe throttle* as the <E is needed to fill IholesI that occur hen the throttle opens quic8l5. Bemem&er to tune

the <E hen 5ou have a tuned "E Ta&le.<nother item to turn off during tuning is the @verrun settings as the ( ma5 drop to #.#mS causing leanspots. ouIll find this &5 going to the 9uel Settings menu - @verrun fuel cut. The default tune has this turnedoff.

Tuning the "E ta&le involves richening )&5 increasing the "E or leaning )&e decreasing "E at each point inthe "E ta&le. Most of 5our driving ill occur in a diagonal strip of the "E ta&le* from lo rpm* lo 8(a )i.e.idle to high rpm* high 8(a )i.e. @T. ou can adAust these values using the @2 sensor* data logs* "E<nal5Le Cive in TunerStudio* and/or the seat of 5our pants. Co rpm and lo 8(a )sa5 less than half of themax rpm and max 8(a might &e a&le to use stoichiometric or leaner.

Bicher mixtures ould &e used at high rpm and high 8(a.

Doever* the lo rpm/high 8(a and high rpm/lo 8(a are not seen as often driving 5our vehicle.

asicall5* if the engine never runs in certain parts of the M<(* then the num&ers there should not matter.Doever* since 5ou ma5 not &e a&le to guess here 5ou ill run under ever5 possi&le set of conditions* 5ouput estimated "E num&ers that ma8e sense into the little used areas.

9rom this frequentl5 used diagonal strip of the "E ta&le* 5ou ill &e a&le to see ho much the "E rises fromone rpm &in to the next* and use these differences to estimate the lo rpm* ver5 high 8(a num&ers and thehigh rpm* ver5 lo 8(a num&ers. Since 5ou rarel5 )if ever run in these parts of the ta&le* the actual num&ers ill not ma8e much difference* &ut the5 ill &e there 1Aust in case1. ou are loo8ing to create a smooth "Emap herever possi&le.

,t is a good idea to set either a ro of 8(a &ins in the "E Ta&le to the idle M<( value. The engine ma5 not

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ala5s idle at the same M<( value hen under load* &ut itIs orth tr5ing to set this up for unloaded idle.Most of the time* an engine ill idle &est if 5ou flatten out the cells a&ove and &elo here it idles' itIs rarefor an engine to need large changes in "E at idle.

3.4.2 /unin' *uel $ Percent (aro

(ercent aro or8s ver5 similarl5 to Speed-+ensit5. The onl5 difference is that &arometric pressure is ta8eninto account for the "E ta&le loo8up. ,nstead of M<( &eing used on the axis* M<(/aro is used instead.

Tuning or8s similarl5 to Speed-+ensit5 - see section 3.4.0

3.4.3 /unin' *uel $ -l%ha$

<lpha- uses the T(S )throttle as the Coad input. ,t can &e a poor estimator of airflo* &ut ma5 &e useful if aM<( signal is unavaila&le or unrelia&le.

Tuning or8s similarl5 to Speed-+ensit5 - see section 3.4.0

3.4.4 /unin' *uel $ M-:

M<9 uses an actual mass air-flo sensor as the Coad input. ,t can &e a more accurate estimate of airflo*&ut is sometimes more complex to configure.

Tuning or8s quite differentl5 from Speed-+ensit5* ta8e note of the folloing explanations.

efore having 5our engine d5no tuned - ma8e sure the d5no operator is clear a&out ho M<9 mode is tuned.

3.4.4.1 M-: trans*er curve

The M<9 transfer curve is used to convert the voltage input from the M<9 sensor into an actual air-flonum&er in grammes per second. ou need to o&tain the actual curve for 5our sensor or the &est estimate.

This curve is found on the asic/Coad Settings menu* once 5ou have ired up and configured 5our M<9sensor. See the TunerStudio Beference uide.

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3.4.4.2 -:R tale +M-:,

,n M<9 mode* the <9B ta&le is 5our main fuel tuning ta&le. ,f 5ou do not hit the actual <9B targets* 5ou illneed to adAust the M<9 flo curve under the asic / Coad Settings menu.

o* letIs ta8e a loo8 at ho 5ou use this particular ta&le.

ouIll enter the <9B 5ou ant at each B(M and load point. Most sequential fire engines ill run &est at04.%!0 at idle. atch-fire engines ill li8el5 need to run richer. <t cruising B(M and lo load* 5ou can run04.%!0 or sometimes leaner depending on the engine. Most naturall5 aspirated engines tend to run &est at03.2 to 03.$ at full throttle* hile engines running forced induction ma5 need to run as rich as the mid 00Isunder &oost.

3.4.4.3 VE trim tale +M-:,

,n M<9 mode* the "E ta&le can &e used to FtrimF the fuelling. efore starting* 5ou M6ST set the ta&le to

0##H in all cells. )Dighlight all cells* press Q* t5pe in 0##* then @.

The ta&le ill appl5 a percent trim to the fueling calculated from the M<9 sensor curve and <9B ta&le.

efore ena&ling this ta&le* ma8e 5our &est effort to dial-in the fuel ith the M<9 transfer curve.

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3.4.4.4 M-:load

,n M<9 mode* the primar5 fuel load is set to 1M<91 &ecause fuel required is directl5 related to mass air flo.Doever* ignition and other load &ased ta&les are not directl5 related in the same a5. hile it ould &epossi&le to use M<9 volts as the -axis on other ta&les* it ould mean that onl5 a ver5 narro &and of theta&le as used and tuning ould suffer. So instead of that* the code calculates a s5nthesised load valuecalled M<9load. This &ehaves similarl5 to M<( in a speed densit5 s5stem and should give a repeata&le loadvalue and allo tuning of those ta&les in the conventional manner. +o not &e too concerned a&out the exactvalues of M<9load* &ut do ma8e sure the axes on the ta&le are set to cover all M<9load values and B(Ms.hen live tuning* the active cell ill &e highlighted.

< M<9 onl5 install ill need to use 1M<9load1 for spar8 and <9B ta&le loo8ups. ut* if 5ou have a M<(sensor installed 5ou could optionall5 choose to set 1Speed +ensit51 for spar8 and/or <9B hich ill then useM<( as the -axis in the ta&le.

3.4." /unin' *uel $ /(

,T tuning mode &uilds on the capa&ilities of the dual ta&le &lended tuning approach &ut solves one of themore significant dra&ac8s to that tuning mode! it provides the &lended Speed-+ensit5/<lpha- &ehavior ofthe &lended dual ta&les in Aust a single ta&le. This single ta&le approach is a significant improvement as allthe automatic tuning tools availa&le through TunerStudio no or8 correctl5 ith the single ta&le. Thesetools are not easil5 used on the &lended tuning approach as TunerStudio does not understand themultiplicative coupling &eteen the to ta&les.

This tuning mode creates a load t5pe called 1,T1. This 1(rimar5 9uel Coad1 )algorithm is selected inasic/Coad Settings - eneral Settings. ,T load is also availa&le for the other tuning settings including<9B* ,gnition* and Enhanced <ccel Enrichment.

The ,T Coad is derived from a com&ination of M<( and T(S values as ell as other ,T-related tuningcurves that all or8 together to create a calculated value that is used as the 1,T Coad1 and applied to the axis of the tuning ta&les.

,T mode uses to additional curves as part of the initial setup &efore the "E ta&le is used for main tuning.nce t&ese cur*es &a*e "een set; you can %ea*e t&e# a%one and focus on tuning t&e E ta"%e in t&econ*entiona% #anner.

@n the left is the ,T Coad T(S Sitchpoint curve* on the right is the ,T load at T(S Sitchpoint

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3.4.".1 /( ?oad /PS Switch%oint Curve

This curve defines the T(S value here the M<( load reaches ?#8(a H&aro sitchpoint. )This is fixed at?#pa in Megasquirt-2. This curve ill &e different for each engine and should &e set up using valueso&tained from log files from 5our engine.

The curve tends to &e fairl5 linear so 5ou onl5 need a fe data points to plot the curve. < data point at lo*medium* and high B(M from a log file is usuall5 enough. < spreadsheet or Aust graph paper can then &eused to esta&lish enough data points to fill in the ta&le for this curve.

@n a ne install* start ith the default curve* then carefull5 run the engine under load to find out hat HT(Sis required to reach ?#8(a at different B(Ms. ou ill li8el5 need to rough in the tune for this step. Thenupdate the T(S sitchpoint curve and recommence tuning.

,T Coad tuning requires that the M<( signal &e a&ove the Haro sitchpoint and that the T(S value &ea&ove the value defined on this curve to sitch from Speed-+ensit5 tuning to <lpha- tuning. Therefore* 5ou ant this curve to &e relativel5 accurate and 5ou ma5 even ant to set the values on the curve a fe percentlo to ensure that the T(S value has &een met hen the M<( reaches the Haro sitchpoint.

esides defining the sitch point to <lpha- tuning* this curve also esta&lishes the loer T(S value that ill

&e used to interpret the range of "E &ins allocated to <lpha- tuning in the "E ta&le.

3.4.".2 /( ?oad at /PS Switch%oint Curve

This curve is used to allocate the &ins on the "E ta&le to either Speed-+ensit5 or <lpha- tuning. The area ofthe "E ta&le &elo the curve ill &e used for Speed-+ensit5 tuning and the area a&ove the curve ill &eused for <lpha- tuning. The shape of this curve defines ho much of the "E ta&le ill &e allocated for use&eteen Speed-+ensit5 and <lpha- tuning for each B(M column. ou ant to allocate the largest portion ofthe "E ta&le at each B(M to the tuning mode that has the most non-linear response. The loer B(M regiont5picall5 requires a little more Speed-+ensit5 definition range than the upper B(Ms.

The current defaults are $#H at all points* so the top of the "E ta&le is <lpha- and the &ottom is the Speed-+ensit5 region.

Un%ess you &a*e good reason to c&ange it; %ea*e t&e cur*e at <0= %oad at a%% RPM points.

3.4.".3 -:R /ale +/(,

,n ,T mode* the <9B ta&le or8s similarl5 to Speed-+ensit5 mode* &ut using ,T load as the axis. Seesection 3.4.0.0

3.4.".4 VE /ale +/(,

,n ,T mode* the "E ta&le or8s the similarl5 to Speed-+ensit5 mode* &ut using ,T load as the axis. Seesection 3.4.0.2

The aim of the ,T mode is to seamlessl5 sitch &eteen Speed-densit5 and <lpha- ith the single tuningta&le.

3.4."." /( technical

Dere are some of the technical details &ehind the ,T mode* 5ou ma5 ant to s8ip these.

The ,T Coad "E ta&le is defined as ,T Coad vs. B(M. The ,T Coad should not &e confused ith M<( orT(S* it is neither. hat the ,T Coad tuning algorithm does is calculate a load value &ased on M<(* T(S*and the to ,T Coad curves. This calculated load value is the axis of the ,T Coad "E ta&le' it can also &eapplied to the ignition advance and <9B ta&les as ell.

I$/ >oad Ca%cu%ation in Speed-,ensity Mode

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hen the throttle position is less than the value defined in the ,T load T(S sitchpoint curve or the M<(value is less than the Haro sitchpoint* the tuning algorithm ill ta8e the arra5 of cells from the "E ta&le&elo the ,T load at T(S sitchpoint curve and interpret this arra5 ithin the context of #H to Harositchpoint load.

,n all cases e ta8e Haro sitchpoint Q ?#

,f 5ou have allocated the region &eteen #H ,T Coad and =#H ,T Coad on 5our "E ta&le for use in Speed-+ensit5 tuning and 5our H&aro is $#H then the "E value for 3#H ,T load ill &e used. ,n this sameexample* a M<( value of #8pa ould use the #H ,T load &in and a M<( value of Aust less than Harositchpoint ould use the "E value Aust &elo the =#H ,T Coad value on the "E ta&le.

I$/ >oad Ca%cu%ation in 6%p&a-8 Mode

hen the throttle position is greater than or equal to the ,T load T(S sitchpoint curve and the M<( valueis greater than or equal to the Haro sitchpoint* the tuning algorithm ill ta8e the arra5 of cells from the "Eta&le a&ove the ,T load at T(S sitchpoint curve and interpret this arra5 ithin the context of T(S position.The loer T(S value used for this interpretation is ta8en from the ,T load T(S sitchpoint curve and theupper T(S value is ala5s 0##H.

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9or example* if 5ou have allocated the region &eteen =#H ,T Coad and 0##H ,T Coad on 5our "E ta&lefor use in <lpha- tuning and also assigned a value of 0#H T(S on 5our ,T load T(S sitchpoint curvethen a T(S value of $$H ould 5ield an ,T Coad value of >#H and the "E &in for >#H ,T Coad ould &eused. ,n this same example* a T(S value of 0#H ould use the =#H ,T Coad &in on the "E ta&le and 0##HT(S ould use the 0##H ,T Coad &in.

3.4.0 (asic acceleration enrichment +-E, tunin'

Megasquirt-2 has &asic acceleration enrichment* plus model &ased acceleration enrichment that eIlldiscuss later.

The &asic time &ased accel enrichment uses varia&les called T(Sdot and M<(dot. The JdotK is a calculusnotation that indicates rate of change ith respect to time. +onIt orr5* 5ou donIt need to 8no calculus totune this. The amount is expressed as a percent of change over time. ith T(Sdot* it is percent openingversus time' a T(Sdot rate of 0## H/sec ould &e opening from closed to ide open throttle in one second*or the equivalent speed* such as going from 2$H to %$H throttle in 0/2 second. The M<(dot is measured in8(a per second. Megasquirt-2 can use either one* or a com&ination of the to* to trigger accelerationenrichment.

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3.4.0.1 Main accel enrich settin's menu

This menu allos all-etting accel enrichment to &e optionall5 ena&led and determines hether the H@Tta&le is used ith T(Sdot.

3.4.0.2 /ime$ased -ccel

The to curves are the primar5 tuning tools. The5 set the pulse idth to add as a function of the rate of

change of M<( and T(S readings. The adder is the ra milliseconds pulseidth adder. 6nder these charts*5ou can set a percentaget to &lend M<( and T(S driven acceleration enrichment. 0##H is entirel5 T(Sdriven* and #H is entirel5 M<( driven. ,n &eteen* the percentage ill scale the M<( driven pulse idthadder don and the T(S driven pulse idth adder up. ;hanging inAector siLe ill require the <E num&er to&e changed.

@nce triggered* the acceleration enrichment ill &e active for a defined time period.

3.4.0.3 ettin' it dialed in

Begardless of hich of the to settings 5ou use* man5 of the aspects of acceleration enrichment tuning ill

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&e the same. efore 5ou start tuning the acceleration enrichment* ma8e sure 5our "E ta&les are dialed in.<dding a correctl5 tuned amount of acceleration enrichment to an incorrectl5 tuned fuel ta&le is still going toresult in an incorrect amount of fuel. Since the acceleration enrichment is stac8ed on top of the fuel the E;6is commanding &ased on the "E ta&le* 5ouIll ant to tune <E last* after 5ouIve got the solid foundation of a ell tuned "E ta&le under 5ou.

The standard <E can &e thought of li8e the accelerator pump on a car&* hich shoots in some extra fuel hen 5ou suddenl5 hit the throttle to compensate for the massive influx of air hen 5ou open the throttle&lades. The goal is to compensate for this influx of air for an instant during that transient until the thetransient is over and the "E ta&les are again providing the proper amount of fueling. ,f 5our &ac8ground istuning car&uretors* 5ou can thin8 of this as a ver5 poerful full5 adAusta&le/tuna&le accelerator pump that lets5ou compensate for more than one rate of throttle position change. Slo Itip-inI can &e adAusted ith acertain ( adder* medium ith another larger ( shot* mid-fast ith another siLe ( squirt* and ver5 fastthrottle movements ith another.

M6P "ased or $PS "ased 6E7 ,f 5ou have a varia&le Throttle (osition Sensor* eId recommend 0##H T(S&ased <E as a starting point. M<( &ased <E does the tric8 if 5ouIre running an engine ithout a usa&le T(S*&ut T(S &ased <E is generall5 eas5 to tune to the proper sensitivit5 level such that it activates hen 5ou ant it to* and not hen 5ou donIt.

Setting t&e $PSdotM6Pdot $&res&o%d >e*e%s 9irst up* 5ou need to determine hat 5our T(Sdot orM<(dot threshold ill need to &e. elo the line graph charts* 5ouIll see a T(Sdot threshold and a M<(dotthreshold. These are the minimum amount of change of T(S position or M<( pressure reading* respectivel5*that are needed to trigger acceleration enrichment. our goal is to set these high enough that theacceleration enrichment onIt accidentall5 trigger at stead5 throttle* &ut lo enough that itIs sensitive enoughto catch small or slo throttle movements as ell. Setting it too high can mean the <E onIt 8ic8 in hen 5ouneed it.ou ant it as lo as 5ou can get it ithout it causing <E to trigger hen itIs not supposed to* such asduring stead5 throttle.

etting this dialed in can &e done methodicall5* or &5 trial and error. DereIs the methodical method.

ouIll need to have a safe a5 to accelerate from the &ottom to the top of a gear* prefera&l5 5our 0!0 ratiogear* and 5ouIll ant to datalog 5our engine idling* as ell as these @T pulls ith 5our Megasquirt-2 andTunerStudio. ,deall5 this is done on a d5no. To to three pulls is &etter than one* &ut thereIs no need to getcarried aa5. Then 5ou can stop the datalogging and load this log up into MegaCog"ieer.

,n MegaCog"ieer* on the left using the drop-don &oxes that let 5ou select hat data 5ou are vieing in5our logs* set one of these to T(Sdot* and/or M<(dot. ou can set another to T(S to sho 5ou hat throttleposition 5ou ere at as ell. <dditionall5* monitoring inAector pulseidth )select ( in the log to vie thatdata is helpful too* as 5ouIll &e a&le to see the commanded inAector pulseidth including the extra fuel addedduing an <E event. Castl5* near the &ottom right corner of MegaCog"ieer 5ouIll see four indicators. T( <E*T( +E* M<( <E and M<( +E. ,f either <E is active* thatIs a <ccel event and <E is adding fuel. ,f either +E isactive* thatIs a +ecel event and <E is pulling fuel if configured to do so.

ext* loo8 at the datalog section of the car idling. The T(S signal should &e roc8 solid* no movement. ,f itIs Aumping around* 5ou have a noise issues on 5our T(S signal. This can &e caused &5 E;6 sensor signal iring thatIs &een routed too close to high voltage sources such as ignition coils* plug ires* the distri&utor*

etc. Be-routing those ires aa5 from those high-voltage sources is ala5s a good idea. <dditionalpossi&lities for noise to get in the T(S signal could &e a &ad sensor ground )&e sure 5ouIve grounded it theMegasquirt-2 sensor return ire @C* or a fault5 throttle position sensor. Similarl5 noise on the M<( signalcould &e electrical* &ut is more li8el5 to actuall5 &e real movement in the manifold pressure* at least at thesource 5ouIre gra&&ing the vacuum signal from* meaning the port on 5our inta8e manifold thatIs connected tothe M<( sensor.

,f 5ouIre seeing <E events at idle* 5our T(Sdot or M<(dot threshold is set too sensitive )too lo of anum&er. ouIll see the pulse idth &ounce around hen this happens as ell' <E is Aust doing hat 5ou toldit to do.

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o loo8 at the datalog sections for the @T pulls* step through these in the logs and loo8 for an5 time <Eactivated )<ccel or +ecel. ,t shouldnIt &e active at all on @T pulls* &ecause 5ouIre at ide @pen Throttle*5ouIre not moving the throttle around* so <E is not needed. <gain* if 5ou are seeing <E activate during @Tpulls* 5our threshold is too sensitve.

,n either case if 5ouIre triggering <E hen 5ou shouldnIt &e* 5ouIll ant to increase the threshold value a &it

a&ove the highest T(Sdot )or M<(dot value 5ou see it reach in the logs. This is the loest 5ou can set 5ourthreshold in order to &e a sensitive as possi&le hile not triggering at stead5 state throttle )or idle* hich isalso stead5 state throttle* itIs the stead5 state of @ throttle.

ote this setting is also the same setting 5ou should use for 5our loest )sloest rate of change T(Sdot orM<(dot field in the next section.

$uning t&e ta"%es o that 5ou have these* itIs time to tune the ( adder line graphs. To tune these* start ith the loest speed throttle change position* and practice Itipping inI at that rate of speed. 6se the real-timeline graph at the &ottom of the page to see ho fast 5ouIre tipping in.

hen 5ouIve &ecome used to appl5ing the throttle at the right rate of speed to &e close to the T(Sdotnum&er 5ouIre using in the IsloI setting* atch 5our ide&and @2 sensor readout. ou ant to &e a&le todetermine hatIs happening hen 5ou sta& the throttle at that rate of speed. ,s it going lean or richG ote

that itIs hard to see this on a gauge* as often it ill go one then the other reall5 fast. ou ant the firstresponse' if it goes lean then rich 5ouIll usuall5 see it hit 2#!0 or ma5&e 22!0 for Aust an instant* and then as itgoes &ac8 to running purel5 the ta&le it ma5 go to 03!0 or hatever... 5ou ant to atch that initial response*and if the first response is to go lean* then 5ou ant to add fuel' if the first response is to go rich* 5ou ant toreduce fuel )p.

< ide&and @2 sensor is immensel5 helpful here* &ut donIt get too caught up in seeing perfect <9B num&ersthrough the hole transient event. <dAust it until it feels right* snapp5 and responsive ith no hesitation. Thefeel is more important than loo8ing for perfect num&ers. ,f 5ou ant perfect num&ers* 5ou ma5 ant to tr5 themodel &ased acceleration enrichment. Setup &asic <E first as descri&ed here. ext 5ouIll adAust the other setpoints 5ouIve setup for faster throttle rate changes.

Bepeat the process for the medium speed tip in* then the mid-fast* then the fast.

3.4.# Startu% @ warmu% *uelin'@n the first couple starts* 5ouIll ant to use hatever com&ination of fuel and throttle can nurse the enginealong until it is armed up* and dial in the fuel at idle hile hot. The reason is that the main fuel tune illaffect startup &ehavior* and 5ou ill ant to have good* solid values in the "E ta&le )at least at idle &efore5ou can get final values for the startup sequence. Dere is the sequence that Megasquirt-2 fueling goesthrough hile starting.

0. hen the 8e5 is on* the Megasquirt-2 ill turn the fuel pump on for 2 seconds and fire one priming pulseto clear air from the lines. )ou can disa&le this feature &5 setting the priming pulse to Lero* this ill also stopthe fuel pump priming.

2. hen the engine starts turning* the Megasquirt-2 ill run off the cran8ing pulse idth ta&le until the B(Mrises a&ove the cran8ing B(M threshold.

3. @nce the B(M rises a&ove the cran8ing threshold* the Megasquirt-2 transitions to the main fuel ta&le. ,t ill initiall5 multipl5 the pulse idth from this ta&le &5 the armup enrichment )6E and afterstartenrichment )<SE com&ined.

4. The <SE tapers off &ased on a user defined curve. <fter the <SE tapers aa5* the Megasuirt-2 ill run onthe main fuel ta&le multiplied &5 6E.

$. hen the engine reaches normal operating temperature* as defined &5 the 6E curve* the engine ill runon the main fuel ta&le* and the armup c5cle is over.

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3." /unin' s%ar6

,gnition is tuned on a 3+ ta&le.

This ta&le specifies the spar8 advance in a&solute num&ers in degrees T+; )&efore top dead center as afunction of B(M and load. The timing 5ou see ith a timing light should match the timing ta&le* unless thereare spar8 trim ta&les in effect that ma8e changes to it. e ordinaril5 recommend tuning the spar8 map on ad5no* &ut here are a fe general pointers for an initial setup.

The idea is that the idle and lo speed areas are set to around >-2#deg. 6suall5 idle ill &e around >-0$Z*&ut this depends on 5our engineIs design. ,f 5ou set the first ro in the B(M range as a little under 5ourusual idle )e.g. =## if 5our engine idles at >##ish and add some advance here this can help sta&iliLe theidle* so if the engine stum&les into this area the slight increase in advance ill help it to speed up a little so itdoesnIt stall. The cruising area of the map should have a reasona&l5 high advance* )lo to high 3#Is as themixture ill &e reasona&l5 lean and therefore ill give a sloer &urn.

The overrun area can have an even greater advance* this ill allo 5ou to run lean in that section. <t ide@pen Throttle )@T the spar8 map needs to &e B(M &ased )analogous to centrifugal advance on an oldst5le distri&utor coming in at the right rate relative to engine B(M. T5picall5* 5ou ant it 1all in1 &5 a&out2>##-32## B(Ms for a street performance motor* although man5 engines ill &enefit from even moreadvance after the torque starts decreasing* something 5ou canIt do ith a mechanical advance.

ote the the optimum amount of total advance is not necessaril5 the most that doesnIt cause detonation. 9orexample* ith a modern c5linder head design* 5ou might get maximum poer at 32ZT+; on a large ">* &utmight not experience an5 detonation until 3>Z- 4#Z. Doever* 5ou ill still ant the advance to come in asquic8l5 as possi&le )ithout 8noc8ing up to 32Z. This num&er onIt &e 32 degrees for all engines' forexample* eIve found that the ne ;hr5sler Demi can have pro&lems at more than 22 degrees of timing atfull throttle* and man5 small &ore engines ith pent-roof com&ustion cham&ers run num&ers in the mid 2#degree range.

hen going into &oost )a&ove 0##8(a* values ill need to &e loer than hen out of &oost. < common ruleof thum& is that 0 degree of advance should &e removed for ever5 2 psi )038(a of &oost' this is simpl5 arough guide* and lots of things can depend on ho much to remove. <dvance &elo 0##H load is oftensimpl5 the flip side of retarding the timing under &oost' as c5linder filling decreases* 5ou ill need moretiming.

Tuning timing under &oost is safest on the d5no here the operator can listen out for 8noc8 and dial in theadvance for &est safe poer.

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3.0 ettin' a 'ood idle

,dle tuning has several components. @ne is ho far the throttle is open - if 5ou have an idle valve* this can &eadAusted ith the ,dle (M +ut5 Ta&le or ,dle Steps hich lets 5ou specif5 the valve opening amount interms of temperature. ,f 5ou donIt have an idle valve* 5ou can use a set scre to adAust the throttle &lade

angle. There is also closed loop idle tuning* hich e ill cover later in the manual. ;losed loop idle tuningtargets a specific idle speed. ut first* 5ou need to get a sta&le idle ithout closed loop tuning. ,f 5our idle isalread5 hunting &ecause of a &ad tune* putting closed loop on an idle that alread5 has trou&le ill ma8e it orse. Start (it& ?pen-%oop 1(ar#up?.

eIll ta8e some time here to explain ho to tune 5our Megasquirt-2 for a smooth idle. The first 8e5 ma5surprise man5 novice tuners! $&e id%e contro% settings are not t&e #ost i#portant t&ing to ad@ust to geta s#oot& id%e.

This ma5 seem counter-intuitive* &ut consider this! ,f the engine is idling at constant load ith the throttle heldat a constant opening* shouldnIt 5ou have a constant idle speedG ,f 5our idle surges or hunts under theseconditions* and 5our idle control valve is sta5ing at one opening value* the idle control settings are not thepro&lem. To get a stead5 idle* 5ou need three things in place! correct fuel* correct timing* and correct airflo.These pro&lems should &e addressed individuall5.

3.0.1 Correct :uel +mi5ture,

Engines donIt li8e to idle lean' a lean air/fuel ratio is one of the &iggest causes of a surging idle. @n anengine ith sequential inAection* this is simple enough - get the engine idling at 04.%!0 for gasoline* and5ouIre good to go. atch fire engines* hoever* have issues at idle ith inta8e pulse reversion sending someof the fuel into an adAacent c5linder. So* if 5our setup onl5 allos &atch fire* 5ouIll need to add a little morefuel so all the c5linders can sta5 at 04.%!0 or richer. atch fire engines t5picall5 idle &est in the mid 03Is* so if5ouIre leaner than that* put in some more fuel and see if that sta&iliLes the idle.

ouIll need to ma8e sure the air/fuel ratio is maintained during cold start. ,f 5our idle hunts hen the engine iscold* &ut sta&iliLes hen it arms up* tr5 more arm up enrichment.

3.0.2 Correct /imin'

Timing is a ver5 useful tool for controlling 5our idle speed. ,deall5* 5ouIll ant the timing to &e set to slightl5&elo the timing that ould give it the most poer - on most piston engines* this t5picall5 or8s out tosomehere in the 0# to 0> degree range. Then 5ou can add a ro around 3## B(M &elo 5our target idlespeed. The timing in this ro can &e &umped up &5 around 2 to 4 degees over the idle timing. The 3d vie&elo shos a spar8 ta&le set up this a5.

Setting up 5our timing li8e this has a sta&iliLing effect on the idle. hen the idle speed drops* the timingadvances* increasing torque and moving the idle speed &ac8 up. The result is an automatic feed&ac8 loopthat helps maintain a constant idle speed. ot ever5 engine reall5 needs this. Doever* 5ou need to loo8 outfor timing curves that do the opposite. ,f 5ouIve specified less timing &elo the target idle speed than 5ouhave at the idle speed* this often ma8es for an unsta&le idle as the E;6 pulls timing hile the idle speedfalls. This can ma8e a slight distur&ance in idle B(M amplif5 itself into an idle speed that c5cles up and don

rapidl5.Too much timing can &e trou&le. ,f the timing at 5our regular idle speed alread5 puts 5ou at the most poeroutput* 5ou have nohere to go &ut don. @ver-advanced timing ill hurt poer as ell - &e5ond a certainpoint* adding more timing ill not &ump up the idle* and ta8en to extremes* it can do the exact opposite. So5ou ant to 1hold &ac81 a little timing at 5our idle B(M and run less than the amount of timing that ould giveit the most poer.

3.0.3 Correct -ir*low

ouIll need to get the right amount of air to maintain a good idle speed.

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Do to do this depends on hat sort of idle valve 5ou have.

o idle valve at allG es* 5ou can run ithout an idle valve. ust use 5our idle speed set scre to adAust itopen enough that the engine doesnIt stall on cold starts. Sure* 5our idle speed ith the engine armed up ill &e higher than it could &e* and 5ouIll have no a5 to adAust for stuff li8e the </; or electrical loads* &ut itIll or8.

The iring of idle valves is covered in the Dardare uide for 5our product.

3.# Batalo''in'

Becording datalogs and revieing them is a 8e5 part of ongoing tuning for most vehicles.

See section 4 in the TunerStudio Beference uide and the )planned MegaCog"ieer Beference uide.

3.#.1 Startin' a datalo'

;lic8ing +ata Cogging Start ill displa5 the Start e +ata Cog dialog as shon &elo!

This ill prompt 5ou to save a TunerStudio ).msl file hich ill contain the data that is logged from 5ourMegasquirt. 5 default the file ill &e saved in the +ataCogs director5 ithin the current proAect director5*although 5ou can choose to &rose and save it elsehere if 5ou prefer. <s soon as 5ou save the file thesoftare ill start to log data from 5our Megasquirt into that file.

hen data logging is running the J+ata CoggingK indicator la&el at the &ottom of the auge ;luster illturn green.

3.#.2 Sto%%in' a datalo'

+ata Cogging Stop ill cease data logging and the collated data file selected in the a&ove section ill &eclosed. our data is no read5 to &e revieed using MegaCog"ieer.

<t this stage the J+ata CoggingK indicator la&el at the &ottom of the auge ;luster ill return to its usualcolor.

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Megasquirt-2 Setting 6p 4!<dvanced topics

A: 6d*anced topicsThe settings for all topics here are covered in the TunerStudio Beference uide* the aim here is to add some&ac8ground and tuning information &e5ond the &asic settings description.

4.1 Sequential :uel

9requentl5 the Megasquirt-2 operates fuel in a &atch-fire mode* &ut some variants support sequential fuel as ell. The different products in the range have different capa&ilities for sequential fuel.

• MS2 - supports up to 4 inAector outputs - +, hardare modifications are required.

• Microsquirt - supports up to 2 inAector outputs* so 2-c5l sequential onl5.

• Microsquirt-module - supports up to 4 inAector outputs ith suita&le external circuits.

• Microsquirt-module ithin +,((* MS((2 etc. - consult 5our supplier for options

;onsult the Dardare uide for 5our product for specific details on iring or an5 modifications required.

$&e fo%%o(ing descriptions co*er t&e (&o%e range and #ay not "e a*ai%a"%e on your &ard(are.

There are options for sequential and semi-sequential inAection* hich allo the use of to additional inAectorchannels.

The code ill do sequential inAection for engines ith up to 4 c5linders )ith the additional inAector channelsand semi-sequential inAection for engines ith up to 02 c5linders. The num&er of inAection pulses per enginec5cle is automaticall5 computed &5 the code &ased on the num&er of c5linders* the num&er of inAectorchannels* the presence of a cam sensor* and the use of staged inAection. Sequential inAection has a singleinAection pulse per engine c5cle and semi-sequential has up to = pulses per c5cle depending on theconfiguration.

The ta&le &elo shos the num&er of inAection pulses per engine c5cle computed &5 the code.

Engine configuration 5it&out Staging 5it& Staging

B Cy% Ca# trigger B In@ B Squirts per20 deg

B In@ B Squirts per20 deg

0 0 2 2 2

0 V 0 0 2 0

2 0 2 2 2

2 V 2 0 4 0

3 V 0 3 2 3

3 V 3 0 - -

4 - - 2 4

4 2 2 4 2

4 V 4 0 - -

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$ V 0 $ 2 $

= 0 = 2 =

= V 2 3 4 3

= 3 2 - -

= V 3 2 - -

> - - 2 >

> 2 4 4 4

> 4 2 - -

0# 0 0# 2 0#

02 2 = 4 =

02 3 4 - -

There are to inAection modes specificall5 designed for siamese-port engines such as the <-series engine ofthe classic Mini and the -series engine of the M. Since these engines have 2 inta8e ports for a 4-c5linderengine ith the c5linders paired having 0># and $4# cran8shaft degrees &eteen the firing events* there is aneed to have inAection timed in a ver5 specific manner and to modes are provided to do semi-sequentialinAection hich does not require a cam sensor and full sequential inAection hich requires a cam sensor.More information on the peculiarities of port inAecting a siamese-port engine can &e found via e& searches.

4.1.1 Con*i'urationThe menu items to configure the sequential inAection are located on asic/Coad Settings - Engine andSequential Settings. The settings on the right are used to configure all the general aspects of sequentialinAection. The "E* trim and inAection timing ta&les are availa&le on the 9uel menu.

4.1.2 nAector timin'

9or sequential mode* the timing value is ith respect to T+; on the poer stro8e hen &oth valves areclosed )same as ignition.

9or sequential siamese mode* the timing is ith respect to T+; on the inta8e stro8e hich is the start of theinAection indo for the outer c5linders. <nd the timing 2 values are onl5 used in sequential siamese mode ith the first timing value &eing for the outer c5linders )0 and 4 hile the second is for the inner c5linders )2

and 3.

4.1.3 Sequential@Semi$sequential /imin'

The image &elo shos ho the timing values relate to the engine c5cle. The timing value of # degreescorresponds to T+; &eteen the compression and poer sto8es. )The same as ignition timing.

(ositive values are for timing in advance of this point up to 3=# degrees hich corresponds to T+; &eteenthe exhaust and inta8e stro8es ith 0># degrees &eing +; &eteen the inta8e and compression stro8es.

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egative values are for timing retarded from the # degree point ith -3=# degrees &eing T+; &eteen theexhaust and inta8e stro8es and -0># degrees &eing +; &eteen the poer and exhaust stro8es.

Sia#ese-port $i#ing

The siamese-port modes use a different reference point in the c5cle due to the position of the inAection indo. The image on the right shos ho the timing values relate to the engine c5cle. The timing value of #degrees corresponds to T+; &eteen the exhaust and inta8e stro8es.

(ositive values are for timing in advance of this point up to 3=# degrees hich corresponds to T+; &eteenthe compression and poer sto8es ith 0># degrees &eing +; &eteen the poer and exhaust stro8es.

egatives values are for timing retarded from the # degree point ith -3=# degrees &eing T+; &eteen thecompression and poer stro8es and -0># degrees &eing +; &eteen the inta8e and compression stro8es.

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4.2 E8 Control

9irst* configure the &asic settings ith reference to the TunerStudio Beference uide.

4.2.1 Sim%le -l'orithm with arrowand Sensor

< narro&and sensor is onl5 accurate at exactl5 stoichiometric mixtures for the fuel &eing used )04.%!0 forgasoline. <t around #.$ volts* the mixture is stoichiometric. 9or leaner mixtures )a&ove 04.%!0 for gasoline*a&ove 0.# lam&da the voltage dips slightl5 &elo #.$ volts. 9or richer mixtures* the voltage goes a&ove #.$volts. This &ehavior means that it is not possi&le to hold an exact mixture hen running closed-loop ith anarro&and sensor.

ecause of this* the &est algorithm to use ith a narro&and sensor is the 1simple1 algorithm.

The simple algorithm adAusts the mixture richer if the sensor reads lean* and leaner if the sensor reads rich. ,tadAusts ;ontroller Step SiLe percent ever5 ,gnition Events per Step. This can lead to a small oscillation in@2-&ased correction once the <9B reaches close to stoichiometric. This oscillation can &e desira&le to 8eepa 3-a5 catal5st operating correctl5.

The folloing steps are recommended hen tuning the simple algorithm ith a narro&and sensor!

#gnition $vents !er Ste! - hen first tuning the engine* this should &e set to a fairl5 lo num&er )4-> so thatif the <9B is ver5 far off* it is corrected quic8l5. @nce the engine is &etter tuned* this num&er can &e sitchedto a higher num&er to gain more sta&le correction &ehavior )>-0= or more.

%ontroller Ste! Si&e - hen first tuning the engine* this should &e set to 2H so that hen correcting* theengine reaches stoichiometric quic8l5. @nce the engine is ell tuned* this should &e reduced to 0H to gainmore sta&le correction.

%ontroller Auth - hen first tuning the engine* this should &e set to 2#H or higher. ;are must &e ta8en to atch ho the algorithm is correcting. ,n some situations* it is possi&le for the sensor to read ver5 lean henreall5 the engine is running ver5 rich. @nce the engine is tuned* this should &e set &eteen $H and 0#H.

$ngagement Settings - Most of the remaining settings control ho and hen the closed loop algorithm isengaged. Engagement ith a narro&and sensor should happen hen the engine is nearl5 full5 arm* $##-

0### rpm a&ove idle* &elo >#H throttle* &elo a&out >#H load* Aust a&ove the loest load seen hen&arel5 pressing the throttle* and at least 3# seconds after the engine starts. These settings are &ecause thesensor must &e hot to operate* must not &e used at high load due to the fact that the engine should &eoperated rich of stoichiometric* and must not &e used at ver5 lo load &ecause the oscillations ill cause theengine speed to oscillate.

4.2.2 Sim%le -l'orithm with 7ideand Sensor

Tuning the simple algorithm ith a ide&and sensor is essentiall5 the same as tuning it ith a narro&andsensor ith the caveat that the <9B target ta&le is used to set the <9B target. ,t is still recommended that theE@ algorithm not &e used at high throttle position/load due to the fact that the accurac5 of the ide&andsensor decreases dramaticall5 ith pressure and temperature changes caused &5 high load.

4.2.3 PB -l'orithm with 7ideand Sensor

,t is recommended to start &5 tuning the F,F term until the target is reached ith minimal oscillation.

<dditionall5* since the response of most ide&and controllers and sensors is linear ith <9B* a larger F(Fterm can &e used to help correct for fast changes in <9B. ;aution must still &e used hoever since there is asignificant dela5 &eteen the amount of fuel &eing inAected changing and Megasquirt registering an <9Bchange as a result.

9inall5* a small amount of F+F term can &e used to help slo response during ver5 fast changes. This helpsreduce overshoot of the target.

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4.3 7an6el Rotar& En'ines

To-rotor engines onl5 are supported on Megasquirt-2 at this time.

$ypica% settings:

Squirts per Engine ;5cle Q 0,nAector Staging Q Simultaneous

Engine Stro8e/Botar5 Q Botar5

o. ;5linders/Botors Q 2

um&er of ,nAectors Q 2

Engine T5pe Q Even fire

Engine SiLe Q 03##cc )true engine siLe

,nAector SiLe Each Q siLe of one primar5 inAector

Sequential ,nAection Q 6ntimed ,nAection

Staged ,nAection ill &e used.

$ypica% settings:

Staged ,nAection 9irst (arameter Q Ta&le

(rimar5 ,nAector SiLe )alread5 set

Secondar5 ,nAector SiLe Q siLe of one secondar5 inAector

See the TunerStudio Beference for more details of these settings.

The tach input and spar8 output ill need configuring also* see the Dardare uide for 5our product forBotar5 specific details.

The oil metering pump is not presentl5 supported* use pre-mix.

4.4 Closed$?oo% dle

efore tr5ing to tune closed loop idle speed control* 5ou must configure open-loop )armup idle speedcontrol. ith open-loop control* a higher step-count or dut5 should 5ield higher B(M. Ma8e sure that this isthe case* and that smooth idle speed can &e attained ith open-loop &efore moving on to closed loopcontrol.

There are to main things to tune hen tuning closed-loop idle speed control!

• ;onditions for entering (,+ control

• (,+ gains

,t is recommended that tuning is done in stages. 9or example* (,+ cannot &e tuned if the code is neverentering the (,+ loop. ecause of this it is a good idea to start &5 tuning the conditions for entering (,+control.

These settings include!

• ,dle <ctivation T(S threshold - Set as lo as possi&le. ,f the T(S has a &it of noise* set it to around

0H* otherise set it to #.3H-#.$H.

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• B(Mdot threshold - 6se this setting so that the code can tell the difference &eteen decelerating

ith closed throttle )engine &ra8ing and sitting at one B(M. Set this as lo as possi&le ithout&eing &elo hat is normal B(Mdot Aitter ith the engine B(M not changing. T5pical values ill &e&eteen $# and %$ B(M/sec.

• Max decel load - The code assumes that if M<( is loer than this setting* the driver must &e

decelerating* and not 1loc8ed out1 of the (,+ loop. Set this to a value Aust under the load seen ithan idle slightl5 higher than the current target B(M R the ,dle <ctivation B(M <dder. This can &e done ith the idle test mode* and setting the valve position manuall5.

• (,+ dela5 - This should &e set so that the B(M dropping on throttle lift can come to a rest slightl5

higher than the target B(M* and &ecome sta&le there. eteen three and five seconds normall5 or8s the &est.

• ;ran8 to Bun Taper - This setting controls ho long after starting the code ill dela5 &efore entering

(,+. eteen three and five seconds or8s ell for this setting.

• (,+ disa&le B(Mdot - < good value for this setting ill t5picall5 &e in the 2##-4## B(M/sec range. ,f

the engine speed suddenl5 accelerates ith no throttle input )li8e if the clutch is engaged hile thecar is rolling and in gear* it must accelerate at a rate greater than this setting &efore the (,+ code

ill &e disengaged. Setting this value too high can lead to stalls after engaging the clutch in thismanner.

To tell hether the code is entering (,+ idle control* the 1;C ,dle1 indicator in TunerStudio must &e used. ,fthe current gauge cluster in TunerStudio does not include this indicator* temporaril5 sitch to a cluster thatdoes.

The idle speed control algorithm as designed to emulate @EM car idle speed regulation. The sequence ofevents that the code as designed to follo are listed &elo!

0. Throttle Cift - @n throttle lift* the code opens the valve to the value learned in the last iteration of the(,+ loop R the dashpot adder. The logic here is that the last learned value should result in an B(Mclose to the target B(M. The dashpot adder is added so that hen B(M settles* it settles to an B(Mslightl5 higher than the target. This is in case the air conditioning as turned on or ,<T increased or

an5thing else that might ma8e B(M loer than the last time the (,+ code ran.

2. B(M settles - <fter throttle lift* eventuall5 the clutch is pushed in and B(M drops to herever it illsettle given the learned value R the dashpot adder. Dopefull5 the idle has settled to an B(M that isless than the commanded target R the ,dle <ctivation B(M adder. ,f so* then the code ill ait for theamount of time specified &5 the (,+ dela5* and then enter (,+ control. ,f B(M settles a&ove thecommanded target R ,dle <ctivation B(M adder* the code then starts chec8ing the (,+ loc8outdetection conditions. <ssuming those condtions are met* the code ill still enter the (,+ loop afterthe amount of time specified &5 the (,+ dela5.

3. (,+ control activates* B(M starts dropping to target - <fter the (,+ dela5 expires* the (,+ code ill&e activated. B(M ill slol5 drop to the target over the num&er of seconds specified &5 the (,+ramp to target time.

4. ormal idle speed reached - B(M reaches the commanded target. (,+ continues regulating B(Muntil the throttle is pressed.

@nce the code is relia&l5 entering (,+ on ever5 throttle lift* it is time to actuall5 tune the (,+ code to reachand hold the B(M target.

The settings that are associated ith or affect the operation of the (,+ algorithm are listed &elo!

• ,dle @pen +ut5/steps and ,dle "alve closed dut5/steps - These should &e set to the minimum and

maximum values that should &e used during (,+ loop and driving operation. ,n addition* havingthese set further apart results in the (,+ loop &eing more sensitive )ma8ing changes to the outputgiven much smaller changes in input.

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• Min dut5/steps for (,+ - This is the loest dut5/num&er of steps that the (,+ loop is alloed to

command. Set this lo enough to result in an B(M slightl5 loer than the loest target B(M.

• B(M ith valve open/closed - These should &e set to the B(M ith the valve closed and the B(M

ith the valve opened respectivel5. ,f using these settings ma8es the code unresponsive to changesin idle speed* the upper B(M value can &e set loer.

• (,+ ;ontrol ,nterval - This controls ho often the (,+ code runs. Setting this too high can result in

sluggish response to sudden changes in load* such as the <ir ;onditioning &eing turned on. Settingit too lo can result in the loop &eing overl5 sensitive to B(M changes. T5picall5 0##ms or8s ell.

• (,+ controller gains - These control the actual response of the code to changes in B(M* as ell as

ho ell the code ill reach the target. Tips for tuning these are listed &elo.

The folloing &asic steps should &e used for tuning the (,+ controller gains!

0. [ero all the gains - Set all the gains to #H. This is so that the effects of tuning the ,-term in the nextstep are not confused ith the effects of an5 other setting.

2. Tune the ,ntegral ), gain - The ,ntegral gain is the onl5 term that controls hether the code actuall5reaches its target. Digher values for ,ntegral gain ill result in the code &eing a&le to get closer to the

commanded target' hoever* a value that is too high ill result in oscillation. The easiest a5 todetermine a good value for the , term is to 8eep increasing it until oscillation occurs* then slightl5loer it. ,f this value is increased to 2##H ithout reaching a point here oscillation occurs* then theB(M ith valve opened setting can &e decreased as far as necessar5* and the open dut5/stepssetting and closed dut5/steps setting can &e made further apart to ma8e the (,+ loop more sensitive.

3. Tune the (roportional )( gain - <fter tuning the , gain so that the B(M reaches the commandedtarget ithout oscillation* the ( gain can &e tuned. The &est a5 to tune this is to set it as high aspossi&le ithout getting an5 oscillation. <fter setting this* tr5 turning on the air conditioning or otheraccessories that normall5 loer B(M or increase load. hen these accessories are turned on* theB(M should dip a &it then recover )the valve position should increase significantl5. 6sing longer (,+ramp to target times can also ma8e it so that hen the (,+ algorithm engages* a higher ( gain can&e set ithout causing oscillation.

4. Tune the +erivative )+ gain - 9or most users* use of the + gain should not &e necessar5. ,tsu&stantiall5 dampens the response of the loop.

Some final tips!

• ,dle 9uel Tuning - efore even attempting to tune ;losed-loop ,dle speed control* tune the area

around idle so that if B(M goes up or don or load goes up or don* the <9B sta5s close to thesame value. ;hanging <9B can affect idle speed* hich can then cause the (,+ code to tr5 tocorrect* getting into an unrecovera&le oscillation.

• Spar8 <dvance - Ensure that the ignition timing around idle is fairl5 smooth. Carge changes could

lead to oscillation.

4." Enhanced -ccel Enrichment +E-E,The Enhanced <cceleration Enrichment feature is &ased on the concept that the fuel inAected does not allenter the engine on ever5 inAector squirt. ,nstead* a portion of the fuel collects on the port and/or inta8erunner alls. The fuel collected there forms a puddle* from hich some fuel enters the engine on ever5inta8e event.

+uring stead5-state conditions )such as cruise or idle* the amount of fuel entering the puddle* the amount offuel leaving the puddle* and the amount of each inAector squirt going directl5 into the engine reach a state ofequili&rium. Doever* during throttle opening or throttle closing transient conditions* the amounts of fuelentering the puddle* leaving the puddle* and going directl5 into the engine change. 6ntil equali&rium is

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reached again* the amount of inAected fuel must change to ensure that the intended amount of fuel )from thenormal fuel equations and "E ta&le loo8up still enters the engine.

9or reference* the accelerator-pump on a car&urettor is a rudimentar5 method to cope ith this same all- etting issue.

The E<E algorithm trac8s the various quantities and adAusts the amount of fuel inAected accordingl5* &ut doesso &ased on several adAustment curves and settings. These are detailed in the next section.

The E<E curves are descri&ed in the TunerStudio Beference uide.

4.".1 /unin' E-E

Since E<EFs main purpose is to ensure that the proper amount of fuel specified &5 the "E ta&le )and otherenrichments actuall5 gets into the engine* it is essential that the "E ta&le as close as possi&le to correct&efore tuning E<E.

Since E<E must trac8 the amount of fuel collected on the port alls in order to function* it is also necessar5for E<E to &e ena&led at all times.

The folloing procedure should &e folloed to tune E<E!

0. Tune "E* armup enrichments* and all other fuel-related features.

2. Turn off normal <cceleration enrichment &5 setting the T(Sdot and M<(dot thresholds to extremel5high num&ers.

3. Ma8e sure that the "E ta&le covers all the a5 don to ;ran8ing B(M and to extremel5 lo 8(avalues.

4. Ena&le E<E in the <cceleration Enrichment dialog &ox.

$. ith the engine at a stead5 B(M in a high gear* step on the throttle SC@C* and note the responsefeel and the <9B.

=. <t the same B(M* lift off the throttle* and note the response feel and the <9B.

%. Tune the E<E <dhere-to-alls curve and E<E Suc8ed-from-alls curve until <9B and response aresmooth and sta&le.

>. Ma8e sure that the throttle movements used are small and slo* alloing the <9B to reach stead5-state &efore moving the throttle again. Ma8e sure that the hole load range is covered* and thatever5 load seen during engine operation is covered &5 each of the curves.

?. ;hoose a fe other B(M ranges* and slol5 step on and release the throttle. Tune the E<E <dhere-to-alls B(M correction and E<E Suc8ed-from-alls B(M correction curves until the response and<9B are correct at the B(Ms chosen. T5picall5 ,dle and high cruise B(Ms should &e chosen. Dighcruise B(Ms for example are hen speed is maintained &ut the gear selection is reduced &5 one orto gears.

0#. Shut off the engine* and allo it to cool completel5. Start the engine' as the coolant temperature

increases* adAust the E<E <dhere-to-alls ;CT correction and E<E Suc8ed-from-alls ;CTcorrection curves so that response and <9B are sta&le.

00. @nce small* slo throttle movements are tuned* larger ones can &e verified* as ell as normaldriving ith gear shifts

02. 9inall5* tr5 to quic8l5 &lip the throttle hile free-revving. ,f response is sloer than desired* a ver5small amount of T(Sdot or M<(dot acceleration enrichment ma5 &e re-ena&led. Ta8e care to onl5use it for high T(Sdot values and use ver5 little. ust enough to get E<E to respond is all that isrequired.

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4.0 (oost Control

The most &asic &oost setup uses spring pressure onl5 and connects the manifold )or tur&o outlet directl5 tothe astegate actuator. 9or s5stems that require more control* the Megasquirt softare offers options forelectronic &oost control.

There are to algorithms for controlling &oost!

• @pen-Coop - Solenoid dut5 comes from an >x> dut5 ta&le )T(SxB(M.

• ;losed-loop - < (roportional-,ntegral-+erivative )(,+ loop controls solenoid dut5 to match the actual

&oost to the &oost target. <n >x> target ta&le )T(SxB(M is used to determine the &oost target.

,n addition to the algorithm selection* 5ou must configure over&oost and several other settings in order to usethe &oost control feature.

4.0.1 Solenoid connection

The iring of 5our solenoid is covered in the Dardare uide for 5our product.

Solenoid and astegate plum&ing are common across the range. There are man5 different plum&ing

schemes availa&le* Aust one is presented here. ,f the iring to the solenoid &rea8s* it should fail safe and runthe engine at minimum &oost )spring.

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hat the solenoid does in different conditions!

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4.0.2 8%en$loo% /unin' /i%s

ith open-loop &oost control* the astegate solenoid output dut5 is directl5 set in a ta&le loo8ed up againstT(S and B(M.

Ensure that more dut5 Q more &oost. #H should give least &oost )spring and 0##H should give maximum

&oost. ,f it does not* chec8 5our plum&ing or flip the @utput (olarit5 setting.

Tr5 out different frequenc5 settings and find the settings that or8 the &est for the particular solenoid &eingused.

To tune the actual &oost levels* Aust adAust the dut5 ta&le so that &oost reaches the desired level at each pointin the ta&le.

4.0.3 Closed$loo% /unin' /i%s

This section revies some tips for tuning closed-loop &oost control. Tuning closed-loop &oost control should

&e done in three steps!

• Tune open-loop &oost control - ,n order to ma8e sure that 5ou have the proper polarit5 set for 5our

valve* and to get a feel for the &oost that certain dut5 c5cles 5ield* it is recommended that open loop&oost control is tuned first.

• Set 6p @ver&oost (rotection - The closed-loop &oost control code uses the maximum &oost set in

@ver&oost (rotection for some of its internal calculations. This as done purposel5 so that during thetuning process for &oost control* if the settings are ildl5 incorrect* &oost ill still not clim& an5 higherthan the @ver&oost (rotection allos it.

• Set the oost ;ontrol Targets. These are the target )desired &oost level at various B(M and T(S

points. T5picall5 loer throttle positions ill have loer &oost targets.

• Tune (roportional-,ntegral-+erivative )(,+ gains - The (,+ gains are the main controls for ho

quic8l5 the &oost ill reach the target* and ho close it ill remain to the target through the B(Mrange. Steps for tuning this can &e found &elo.

C%osed-%oop settings

T5picall5* the defaults for the folloing settings can &e used!

• %ontrol #nterval - The default for this setting is 2# ms. This is t5picall5 a good place to start. Coer

settings can &e used if overshoot cannot &e tuned out hen tuning the (,+ parameters.

• %losed Duty - < closed dut5 of #H is the default. This should &e tuned to the value that starts to open

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the astegate* &ut t5picall5 #H or8s ell.

• '!en Duty - <n open dut5 value of 0##H is the default. This should &e tuned to the value that full5

opens the astegate* &ut t5picall5 0##H or8s ell.

• (oost %ontrol )ower )imit - oost pressure must &e ithin this man5 8(a of the target &oost &efore

closed loop control ill activate. @utside of this range the valve is held ide open )8eeping the astegate shut for fastest spooling.

@TE! The output polarit5 setting onl5 changes the actual dut5 on the output. Begardless of this setting* the&oost control algorithm is designed to operate on the assumption that more dut5 Q more &oost.

$une t&e PI, gains!

0. Set ,ntegral and +ifferential ains to #H - To ma8e tuning the (roportional gain easier* set the,ntegral and +ifferential gains to #H.

2. Set (roportional gain to 0##H and slol5 loer - hile tuning (roportional gain* higher num&ersmean sloer &oost clim& and loer final &oost. 9or safet5* start ith a ver5 high gain )0##H should&e sufficient. 9ind the B(M that t5picall5 spools quic8l5* and full5 and quic8l5 depress theaccelerator. ote ho much &oost is reached. ,f &oost overshoots the target dramaticall5* increase

the (roportional gain. @therise* reduce the (roportional gain and tr5 again. +o this until &oostreaches the target ith a small amount of overshoot.

3. Tune the ,ntegral ain - The next step after the target is reached consistentl5 is to tune the ,ntegralgain. Starting from the B(M used to tune the (-gain* full5 depress the accelerator and atch the&oost as the engine clim&s through the B(M range. <s the engine accelerates through the revrange* the &oost ill pro&a&l5 creep aa5 from the target. eep increasing the , gain until thecontroller adequatel5 maintains the target ith minimal oscillation. ,t ma5 &e necessar5 to increasethe ( gain a &it after tuning the , gain since the to gains tend to counteract each other.

4. Tune the +erivative ain - ,ncrease the + gain until the overshoot is minimiLed. ;are must &e ta8en hen increasing the + gain as too much + gain can over-dampen the effects of the ( and , gains.

4.# itrous 85ide +28,itrous oxide is a poer-adder frequentl5 used in drag racing to add $#-0##H poer to an engine for shortdurations. Used incorrect%y it can #e%t pistons and destroy engines in seconds.

The nitrous s5stem ithin Megasquirt allos control over the nitrous and optional fuel solenoid to ena&le thenitrous inAection hen desired and also retard the ignition timing. The s5stem supports to stages of on/offcontrol.

9ull5 tuning nitrous is a topic &e5ond the scope of this manual* e shall Aust cover some &asics.

4.#.1 S&stem t&%es

There are to main categories of nitrous s5stems - et and dr5.

5et < et s5stem inAects fuel into the manifold ahead of the inAectors )e.g. under the throttle &od5* this can resultin fuel distri&ution pro&lems and mixture var5ing &eteen c5linders.

The simplest example of a et s5stem is a 1plate1 s5stem that installs unders the throttle &od5 )or car&a&ove the inta8e manifold and utilises spra5 &ars for nitrous and fuel. @ther variations exist here single ormultiple noLLles are utilised.

< standalone et nitrous s5stem has the advantage that hen used ith the suppliersF suggested Aetting it ill t5picall5 install and or8. )More hardare* less tuning.

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4. Variale Valve /imin' +VV/; VC/; V/EC; V-8S,

The Megasquirt-2 can support on/off t5pe varia&le valve timing s5stems* these are t5picall5 earlier @EMs5stems.

@n/off s5stems can &e configured using one of the (rogramma&le on/off outputs. Set the conditions so thatthe output is ena&led a&ove a set B(M and Coad. See the TunerStudio Beference uide.

ire up the solenoid similarl5 to a &oost solenoid - see the Dardare manual for 5our product.

9ull5 varia&le ""T is not supported &5 Megasquirt-2. Most later @EM s5stems are full5 varia&le. The E;6monitors the position of the cam and operates the solenoid)s to adAust the exact position. ,f 5our engineuses one of these s5stems* 5ou ma5 &e a&le to mechanicall5 loc8out the ""T to a fixed position* &utgenerall5 5ou are advised to upgrade to Megasquirt-3 for full control.

4.9 C- (us E5%ansion

;< is a to ire in-vehicle communications s5stem that allos different vehicle computers to 1tal81 to eachother. ,n essence it is an expansion iring s5stem.

Megasquirt comes ith ;< and allos it to communicate ith other )Megasquirt ;< ena&led devicessuch as 3rd part5 dashes* ;<ET* (,@* perfFs ,@-x and li8el5 other add-on &oards.

enefits!

• Simple connection. ust connect the to ires.

• ;onnect additional sensor inputs or control outputs.

• Multiple Megasquirt devices can share sensor and other data over the ;< netor8.

• ou can tune multiple Megasquirt devices concurrentl5 ith 5our computer plugged in to one.

There are to main modes used over ;<•

+evice-to-device - here the E;6s exchange data ith each other autonomousl5• (assthrough - here TunerStudio is used to tune a device remotel5 over the ;< netor8

4.9.1 C- %rotocol

The Megasquirt s5stem as standard uses a proprietar5 messaging s5stem using 2?&it headers. This ma8es itincompati&le ith man5 other third part5 ;< devices.

< small num&er of standard 00&it header &roadcast messages are supported in firmare 0.3.x

,n firmare 3.4.x greater support is added to &roadcast standard 00&it header messages for greaterinteropera&ilit5. Belease is planned for 70 2#0$ as a free upgrade for Megasquirt customers.

9urther details of the internals of the Megasquirt-;< s5stem are availa&le in a technical note.

4.9.2 Bevice$to$device

,n this mode to devices on the ;< netor8 exchange data independent of the tuning computer.

e.g. < transmission controller fetching engine data from the Megasquirt* or the Megasquirt polling devices onthe netor8 and datalogging the results.

@nce configured the data transmission ill happen as and hen required ith no user intervention.

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The to devices request and receive data on theiron* independent of an5 tuning computer

4.9.3 Passthrou'h

,n this mode messages from 5our tuning computer are rela5ed to remote devices over the ;< netor8.

e.g. tuning the remote device from 5our laptop.

This can &e reall5 useful hen 5ou have more than one Megasquirt device on 5our vehicle* ith a singleconnection point for 5our tuning computer 5ou can 1connect1 to an5 of the devices on the netor8 and viedata* tune etc. ou could also use the computer to datalog from multiple devices concurrentl5. The loggingspeed ill &e reduced the more devices 5ou tr5 to log from.

TunerStudio allos ;< devices to &e added to the main proAect so 5ou can vie and tune multiple ;<devices concurrentl5. Megasquirt-2 has limited ;< data capture options )compared to Megasquirt-3 somostl5 5ou ill &e datalogging data captured from remote expansion &oards.

The tuning computer is connected to the Megasquirt either &5 serial or 6S-serial.The Megasquirt and remote device are connected &5 the to ires of ;<.

Step '. Tuning computer sends 6S/serial request to

Megasquirt )addressed to remote device.Step 2. Megasquirt recogniLes this as a passthroughrequest and rela5s it on to the remote device over;<

Step . Bemote device ansers request and sends &ac8 data

over ;<.Step A. Megasquirt receives data and forards it on to tuningcomputer &5 6S/serial.

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4.9.4 C- wirin'

e5 points to note.

• ;<D to ;<D*

• ;<C to ;<C

• @ne 02# ohm termination resistor at each end of the 1&us1 - this ill almost ala5s &e inside the &ox.

The Megasquirt 3 comes ith the resistor alread5 in place* so no action is required.• ote that neither ire is connected to ground.

• ,f 5our Megasquirt-3 is pre-assem&led* ensure that the ;< connections are actuall5 present inside

the &ox.@therise - complain to 5our vendor:,f 5ou assem&led the &oard 5ourself* then ma8e sure that @6 installed the Aumper ires.@n "3.# and "3.$% &oards 5ou need the folloing Aumpers

• S= - S(B0/;<D

• S> - S(B2/;<C.

• ,f 5ou onl5 have to devices connected then the 1&us1 ill simpl5 &e to ires running from one &ox

to the other* as shon in the example diagram a&ove.• ,f 5ou are connecting three or more devices 5ou ill need to connect them as a&ove and ensure onl5

the to end devices have terminators and the middle ones do not.• 9or short runs of ca&le a simple pair of ires is li8el5 o8* for large runs it ma5 &e advisa&le to use

tisted pair or tin core screened ca&le.

4.9." C- settin's and data t&%es

The Megasquirt-;< netor8 t5picall5 or8s &5 passing along sections of memor5 ta&les. <s a result* man5of the settings ill deal ith telling the Megasquirt here the ta&le is in memor5 and ho to retrieve it.

4.9.".1 P7M %ollin'

<llos frequenc5 data to &e collected from an expansion device.

4.9.".2 Bi'ital %orts

This allos the MS2 to use up to eight remote on/off inputs and up to sixteen remote on/off outputs.

4.9.".3 P7M out%uts

<llos (M/frequenc5 outputs to &e used on an expansion device. e.g. (M ,dle.

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4.9.".4 C--BCs

<llos analogue data to &e collected from an expansion device. The captured data can then &e dataloggedas gpioadc#-%.

4.9.0 C- (roadcastin'This allos a handful of pre-defined standard 00&it ;< messages to &e &roadcast for specific customerapplications. )More could &e added - please as8.

4.9.# E5am%le Settin's $ D(%er* 8e5tender

The E)tender from (EB9 ma8es use of the Megasquirt ;< s5stem and allos the MS3 to collect thedata from the ExtenderFs inputs. The Extender has up to!> general or thermistor inputs> thermocouple ET inputs3 axis accelerometerBealtime cloc8lo&al (ositioning S5stem

Befer to the Extender documentation on the (EB9 site for initial configuration.

6,C inputs

6p to 24 analog channels are availa&le from the ,@-Extender. 6p to > can &e collected &5 the MS2 andrecorded in a datalog as a ra <+; value. )MS3 can do more.

Ena&le <+; polling Q Ena&led

MS2 gpioadc Can id $a"%e ffset E)tender 6,C 4unction

gpioadc#-3 $ % 2 <+;#-3 general <+; inputs

gpioadc4-% $ % 0# <+;4-% general <+; inputs

- $ % 0> <+;>-00 ET inputs

- $ % 2= <+;02-0$ ET inputs

- $ % 34 <+;0=-0? attv* accelerometer inputs

- $ % 42 <+;2#-23 3v3 ref* general <+; inputs

@TE! e sure to set the Extender to 0#&it <+; for compati&ilit5 ith Megasquirt.

,igita% ports ou can configure ports 0 and 2 as digital output ports )0= channels and port 3 as a digital input ith thefolloing settings.

;< device Q $

Ta&le Q %

Ena&le input port Q Ena&le

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@ffset Q %%

Ena&le output port Q To

@ffset Q %$

4.9. E5am%le Settin's $ other devices,nformation request - if 5ou have settings that or8 ith other standard Megasquirt devices* please post onthe .msextra.com forum* so that information can &e included here.

4.1! Readin' and Batalo''in' an -dditional Sensor

The Megasquirt-2 E;6s t5picall5 have to FspareF <+; )analog inputs that 5ou can use to read and datalogan additional analog sensor. e.g. pressure* temperature. )9or reference* the configuration in Megasquirt-3 isfar simpler.

4.1!.1 7irin'

Befer to the Dardare Manual for 5our product for details on ho to ire in an additional analog sensor. Theprocessor requires a #-$" signal.

4.1!.2 /unerStudio custom.ini

The additional sensor signal is converted to a digital num&er )#-0#23 &5 the Megasquirt-2. To convert thatra num&er into something more meaningful* 5ou need to create or edit a file called 1custom.ini1 thatinstructs TunerStudio to process that num&er. ou can then displa5 a gauge on 5our tuning computer andrecord the value in datalogs.

efore 5ou start* ma8e S6BE that 5ou turned off the option to 1Dide 8non file extensions1 in indos.

6se a text editor )e.g. otepad on indos and create some custom configuration. The Fcustom.iniF fileuses a 8ind of programming language. The equations are case sensitive and can silentl5 fail if 5ou get thecase rong:

e.g.

The a&ove example reads from the to spare analogue inputs!

adc= Q S$ / S(<BE<+;

adc% Q S4 / S(<BE<+;2

The varia&les Fadc=F and Fadc%F are alread5 defined in the main FiniF file and are equal to the ra <+; countfrom the analogue inputs.

The @utput;hannelsU section gives definitions of ne varia&les. Dere F@ilTempF is defined as a ta&le loo8up

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from a provided loo8up ta&le file 1ntc&osch.inc1. F@ilpressF is a linear equation.

The +atalogU section specifies hat additional fields should &e added to the datalog.

)ot shon the auge;onfigurationsU section defines addtional gauges that 5ou can add to theTunerStudio dash.

auge;onfigurationsU

oiltempauge Q oilTemp* 1@il Temperature1* 1Z91* -4#* 00#* -0$* #* 2##* 3##* #* #

Daving created the file* 9ile- Save<s custom.ini in the TunerStudio(roAects/\5our proAect/proAect;fgdirector5.

4.1!.3 ?oo6u% tale .inc

The ntc&osch.inc file is a loo8up ta&le of 0#24 ros that converts the ra <+; value into a useful actualvalue. The to columns are T< separated.

X<+; "alue MS"al volts

# 0>#.##0 0>#.##...>23 0#.4$>24 0#.22>2$ ?.?>>2= ?.%$>2% ?.$2

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>2> ?.2?>2? ?.#$...0#22 0>#.##0#23 0>#.##

9or temperature ta&les such as this one* it is t5pical to have the ver5 end points as a default tempertature)0>#Z9 in this case so that if the sensor iring fails or shorts to ground* a 8non FfailsafeF value ill &edispla5ed.

This F.incF file needs to &e saved to the FincF su&-director5 under 5our proAect folder.

e.g. +ocuments/TunerStudio(roAects/\5our proAect/inc/

These include ).inc files can &e created &5 editing a log file generated &5 the TunerStudio thermistor ta&legenerator and stripping out un-needed ros and columns.

4.11 Pro'rammale 8n@8** 8ut%uts

This screen is for setting up generic on/off outputs for features li8e shift lights* varia&le inta8e control

solenoids* and other items that donIt need complicated control settings. These settings are not required hen the outputs are used for other &uilt-in features.)e.g. do not tr5 to configure a spare port 9,+CE if 5ou ant to use 9,+CE ith the idle-control s5stem. ,f 5ouhave configured an output to &e used for to features the code ill report a Fconfiguration - fix the mista8e in5our settings.

T5picall5 the output ill &e ired to a rela5* a small lamp or a solenoid.

<ll of the MS3 realtime data channels can &e used as parameters. it-field varia&les can &e used also iththe FYF operator. e.g. 5ou could configure a lamp to light up if 5ou hit the rev limiter.

4.11.1 (itwise o%erations

The &itise <+ operation requires some further explanation and an example. Ta8e the 1engine1 data

channel. 9rom the TunerStudio Beference manual* 5ou can see the definition!

12 64 32 16 4 2 1

M% de-e'enri-#ment

M% a--e'enri-#ment

TS de-e'en'eanment

TS a--e'enri-#ment

7"+ a-tive %S+ a-tive raning &ead!(a-tive ta-#signa' and

umrunning*

,f 5ou are unfamiliar ith &its* &5tes and &inar5* then some &ac8ground reading ma5 &e required.

9or &itise operations*

result Q ))value Y TDBESD@C+ QQ DST

Sa5 5ou anted an output to activate hen 5ou are in 6E )armup mode* &ut not T(S accel.

T(S accel has a value of 0=. 6E has a value of >.

e ant to chec8 &oth of these &its* so need to set the 1threshold1 )&itmas8 to 0= R > Q 24.

e then ant to chec8 that T(S accel is clear and 6E is set* so set the 1h5st1 )match Q >.

12 64 32 16 4 2 1

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Megasquirt-2 Setting 6p $!Trou&leshooting

<: $rou"%es&ooting

".1 Resets

< reset is hen a disruption in poer or a spi8e in voltage causes the processor to &riefl5 shut don. This ill cause the engine to hiccup hile running* and ill displa5 a couple other s5mptoms. The Megasquirt-2 ill reset hen it is poered up* and this is the right time for it to reset. Daving it reset on a running engine*hoever* is something 5ouIll ant to fix right aa5.

• The Megasquirt-2 ill &riefl5 disconnect from the laptop or other devices on 6S or BS232.

• +ata logs ill indicate a JMar8 )num&er - BESETK.

• The SecC count ill drop to Lero.

The last item is a 8e5 part for spotting true resets in a data log. ,f the engine hiccups* &ut the SecC countdoes not drop &ac8 to Lero* 5ouIve got something else* such as a fuel cut* loss of B(M signal* or other issue.,f itIs a real reset* here are the items e recommend chec8ing first.

9irst* ma8e sure the Megasquirt-2 has all ground ires used* and grounded to the engine &loc8 or c5linder

head. ;hassis grounds can have issues caused &5 rust or points here current runs through nothing &ut athin spot eld.

;hec8 here the Megasquirt-2 is getting poer from a clean source - ideall5* 5ouIll ant it to &e poered offthe &atter5* ith no devices that dra significant current getting poer from the same feed. Man5 resetscome not from EM, / B9, interference* &ut from something li8e an ignition coil* fuel pump or ide&andcontroller inAecting voltage spi8es into the poer feed.

Ma8e sure that 5ou are using resistor t5pe spar8 plugs* good spar8 plug ires )if 5ouIre not running coil onplug* and that the spar8 plug ires are not ithin one inch of an5 ires going to or from the Megasquirt-2.

".2 RPM$S&nc issues

;ertain conditions such as electrical noise can cause the Megasquirt-2 to lose s5nc ith the engine position.This is called a s5nc loss event or a s5nc error. The 1B(M-s5nc1 indicator on the dash ill &riefl5 turn red.;ommon s5mptoms of this include!

• 9eels li8e a misfire or a false rev limiter

• B(M in datalog suddenl5 drops to Lero

• B(M in datalog suddenl5 spi8es up

• 1Cost s5nc count1 increments hile 1SecC1 counts up normall5. ). ,f SecC suddenl5 drops to Lero

this is a 1reset1' see section >.0.

Ta8ing and revieing a datalog is a required step for trou&leshooting this. This datalog extract &elo )vieed

in Megalogvieer shos the rpm )5ello trace dropping to Lero and at the same time the 1Cost s5nc count1increases. The 1Cost s5nc reason1 shos reason code 2.

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".2.1 ?ost s&nc reasons

The Megasquirt-2 can report several different lost s5nc reasons in the data logs. Most of these simpl5 shothat thereIs a pro&lem and donIt particularl5 pinpoint here it is* &ut some are more specific than others. ,nparticular* if 5ou get Cost S5nc Beason 00 or 0% in a specific B(M &and* tr5 changing the ignition input

capture and /or second trigger active edge.# no pro&lem

2 missing tooth at rong time

0# too man5 teeth &efore end of sequence

00 too fe teeth &efore second trigger

02 too man5 s5nc errors

03 diLL5 rong edge

04 trigger return vane siLe

0$ and 0= - E+,S S< signal error

0% second trigger not found hen expected

2# su&aru =/% tooth = error

20 su&aru =/% tooth 3 error

22 Bover X2 missing tooth error

23 42#< long tooth not found

24 42#< cam phase rong

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2$* 2=* and 2% pattern does not otherise match 42#<

2> (attern does not match 3=-0R0

2? 3=-2-2-2 semi s5nc failed

3# 3=-2-2-2 tooth 04 error

30 Miata ??-## - 2 cams not seen

32 Miata ??-## - # cams seen

33 =%2 - tooth 2 error

34 =%2 - tooth 4 error

3$ (attern does not match e&er-Marelli

3= ;<S 4/0 error

3%* 3>* and 3? (attern does not match 4=3

4# and 40 Tin trigger error

42 (attern does not match ;hr5sler 2.2/2.$

43 (attern does not match Benix

44 (attern does not match SuLu8i Sift

4$ and 4= (attern does not match "itara

4% (attern does not match +aihatsu 3

4> (attern does not match +aihatsu 4

4? (attern does not match "TB0###

$# (attern does not match Bover X3

$0 (attern does not match M %N

$2 3=-2-2-2 tooth 3# error

$3 rc$0 semi error

$4 rc$0 re-s5nc error tooth =

$$ rc$0 re-s5nc error tooth 0=

$= rc$0 re-s5nc error tooth 0>

=0 ; cran8 pattern

=2 ; cran8 pattern

=3 7B2$+E

=> CS0 res5nc failed

=? [90### res5nc failed

%# 3=-0R0 no cam

Daving identified that 5ou have a s5nc loss pro&lem* 5ou need to attempt to eliminate it. ;hec8 for an5 &asicpro&lems!

• Coose sensor

• Coose ca&ling

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• Sensor ires running close to spar8 plug ires or coils

• Slop in timing &elt

• "B sensor ired &ac8ards

• 9ouled plugs causing misfire

• on-resistor plugs

• Excessivel5 rich mixture causing misfire

• Excessivel5 lean mixture causing misfire

Daving ruled out all those possi&le causes* 5ou should use the tooth and composite loggers to record theincoming cran8/cam pattern and loo8 for the pro&lem. ou ma5 ell ant to ena&le some noise filtering. Seethe TunerStudio Beference uide for additional information on the high speed loggers and noise filteringsettings.

Example composite log shoing noise causing loss of B(M-s5nc.

".3 oise :ilterin'

The noise filter settings can &e used to 1clean up1 the incoming tach signal to remove interference anddefend against B(M-s5nc issues.

The exact settings are ver5 install specific* eFll cover some of the &ac8ground theor5 of hat the settingsdo. The naming of the inputs ma5 refer to different hardare versions* &ut the concepts remain the same.

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The Megasquirt needs to &e configured for rising edge in this instance as that matches the FsharpF elldefined Lero crossing of the input signal. e can no loo8 at hat the Megasquirt code ill see.

This shos ho the rising edge configuration results in hat eFll call a Fsingle edgedF signal. The Megasquirtis onl5 aare of that rising edge and pa5s no attention to the length or the high or lo periods or the fallingedge.

o* insert some noise.

The noise pulse creates a false trigger to the Megasquirt* this could cause an rpm &lip on the fuel onl5 install*a misfire or a total loss of s5nc on the more advanced installs.

Daving esta&lished hat the noise signal might loo8 li8e* ho to get rid of itG

These are the main methods availa&le to improve situations

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• noise filter

• tach mas8ing

• tach period reAection

• polarit5 chec8

".3.1 oise *ilter

The noise filter or8s on the principle that the noise is li8el5 to &e of short duration* far shorter than agenuine tooth. ,f all input conditioners are setup correctl5* e should &e a&le to detect this condition &5measuring the idth of the input pulse. < FlongF pulse is real* a FshortF pulse is noise.

".3.2 /ach interru%t mas6in'

This approach is slightl5 different. ,t does not calculate the pulse idth* &ut loo8s at here it is ithin theperiod. ,f e have suddenl5 received an earl5 pulse )ithin 3#H of the expected time then it must &e noiseand is reAected. The code disa&les the hardare interrupt for this calculated mas8 period and an5 inputs thathappen hile the interrupts are off are 1 invisi&le.1 There is a dra&ac8 though* on the uneven heels thecode calculates this time &ased on the smallest tooth. < pattern such as 42#< has idel5 var5ing tooth siLes*so the &enefit is reduced. )<dditionall5* &ut less importantl5* the tooth logger cannot record the noise inputsas the5 are not captured.

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".3.3 /ach %eriod reAection

This is similar to the concept &ehind interrupt mas8ing* &ut the interrupt is still ena&led. The code comparesthe times and reAects it if it falls ithin the reAection period.

".3.4 Polarit& Chec6

This method should eed out extremel5 short noise pulses. ,f the input signal changes state ver5 quic8l5* thepulse ill alread5 have completed &efore the Megasquirt has had time to react. 5 polling the input pin to the;(6 the code chec8s to see if the polarit5 is the expected one* if not it must &e noise and the input isignored. This method is automaticall5 ena&led.

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".4 Communications issues

Sometimes on a ne install* 5ou ma5 have difficulties esta&lishing communication ith the Megasquirt. Thefirst step is to ensure that 5our computer is 1seeing1 the serial interface or adapter.

".4.1.1 7indows device

@n indos s5stems* +evice Manager ill sho comms ports under 1(orts1.

,f nothing is shoing under 1(orts1 then 5ou li8el5 have a configuration or driver pro&lem on 5our computer.ou need fix that first. Ma8e sure the 6S ca&le is securel5 inserted or tr5 a different soc8et. ,f that doesnFtresolve it* tr5 de-installing and then re-installing the device driver.

".4.1.2 Mac 8S device

6S-serial adapters should sho up as files such as /dev/tt5.us&serialNN

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".4.1.3 ?inu5 device

6S-serial adapters should sho up as files such as /dev/tt56S#

".4.2 ?oo%ac6 test *or serial or S($serial cale

ith a direct serial or a 6S-serial ca&le )not direct 6S* 5ou can perform a loop&ac8 test to see if serialdata is getting out from 5our computer and can &e 1looped-&ac81 in again.

;arefull5 short together pins 2 Y 3 of the plug in 5our ca&le.

Start TunerStudio and open ;ommunications - Miniterminal.

Select the port as a&ove )i.e. if 5our connection as ;@M$ in device manager* then choose ;@M$ here.

Select the &aud rate to 00$2##.

;lic8 to @pen the port.,n the upper pane* t5pe in FtestF

,f the serial port is or8ing correctl5* 5ou should see FtestF come &ac8 in the loer pane.

,f nothing comes &ac8 in the loer pane* dou&le chec8 that pins 2Y3 are shorted together. ,f the5 are* then

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1 2 3 4 5




5our 6S-serial adapter or serial port ma5 &e fault5. Tr5 on a different computer. @r tr5 a different 6S-serialadapter )9T+, &ased are recommended.

".4.3 ?oo%ac6 test to Me'asquirt oard +not Microsquirt,

ith a direct serial or a 6S-serial ca&le )not direct 6S* 5ou can perform a loop&ac8 test to see if serialdata is getting out from 5our computer and through the Megasquirt &oard and can &e 1looped-&ac81 in again.

"er5 carefull5* prise out the MS2 ;(6 card 60. Cift it out progressivel5 &5 pr5ing up each end a fraction at atime. e certain not to &end the pins.

,nstall a Aumper &eteens pins 02 Y 03 of 60

Ma8e sure there are no short circuits or loose ires around* then turn on 5our Megasquirt )connect a fused02" suppl5.

<s in section $.4.3* open up TunerStudio and perform the loop&ac8 test in MiniTerminal.

,f test $.4.3 or8ed o8* &ut $.4.4 does not or8* it suggests there ma5 &e a pro&lem on the Megasquirt&oard. Either there is no poer* a solder connection is fault5 or the serial chip )6= is damaged.

;arefull5 re-install the MS3 ;(6 card 60 after testing is complete.

".4.4 Comms test to Me'asquirt @ Microsquirt

This test requires that firmare is alread5 installed )section 2.>. ,f 5ou are una&le to install firmare* thenrevie the previous sections.

Start TunerStudio and open ;ommunications - Miniterminal. Ensure 5our Megasquirt is poered andconnected to 5our computer.

Select the port as a&ove )i.e. if 5our connection as ;@M$ in device manager* then choose ;@M$ here.

Select the &aud rate 00$2##.

;lic8 to @pen the port.

,n the upper pane* t5pe a capital FSF and 5ou should see a signature string returned in the loer indo asshon here. ,f 5ou do not then there is a serial pro&lem somehere.

)The text returned here is the firmare version string* the same as ill normall5 &e shon in the TunerStudiotitle &ar.

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Megasquirt-2 Setting 6p =!<ppendix <! 9irmare upgrade notes

D: 6ppendi) 6: 4ir#(are upgrade notesThis section of the manual covers an5 specific issues 5ou ma5 encounter upgrading to the current firmareversion from older releases.

8e( users do not need to read t&is section.

eteen each maAor firmare version there ill li8el5 &e significant changes* some ma5 require an elementof re-tuning. Beleases ithin each firmare version )e.g. 3.3.#* 3.3.0* 3.3.2 are released to resolve an5issues that &ecome 8non and should &e usea&le ithout an5 settings changes or re-tuning.

0.1 :irmware versions

MS2E)tra fir#(ares Status Co##ent

0.#.x @&solete @ld release code

2.#.x @&solete @ld release code

2.0.x @&solete @ld release code

3.#.x @&solete @ld development code



3.3.x Superceded @ld release code

3.4.x ;urrent The current release code famil5

0.2 -l%ha; eta; release code> 7hat=s the di**erence>

+uring code development there are a num&er of 8e5 phases as the firmare evolves. The naming isintended to identif5 hich stage the firmare is at.

• Belease - the firmare is considered suita&le for general release* features are complete and

&elieved to or8 as descri&ed. 8e( users s&ou%d "e using re%ease code.

• eta - the firmare is considered suita&le for moderate release* features have &een completed* &ut

extended testing is required to ensure ever5thing or8s as descri&ed.

• <lpha - an5thing goes. e features* incomplete code* test code. The latest features ill &e made

availa&le as an alpha release* &ut it is up to the tester to determine if it or8s correctl5. e users

are advised to avoid alpha releases.

0.3 %'radin' *rom 3.3.5

ou can mostl5 load 5our MS2/Extra 3.3.x tune into MS2/Extra 3.4.x.

0. aro

(reviousl5 the code used to divide &5 the &arometer hen calculating the fuel pulseidth. ,f using an oldtune 5ou need to ena&le the 1old st5le1 &aro calculation to ena&le the old &ehaviour.

2. ;CT rev limiter

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The T(S &5pass rev limit setting has &een removed* the standard hard limit is no used in &5pass mode toreduce confusion.

3. < detailed list of changed features is provided in the TunerStudio Beference manual.

0.4 %'radin' *rom 3.2.5 ou can mostl5 load 5our MS2/Extra 3.2.x tune into MS2/Extra 3.3.x

0. M<9

There is an exposed M<9 cali&ration implementation li8e MS3. The old method ma5 still &e used if desired.

2. arometric correction

The recommended settings for &aro correction in 3.3.x have changed.

0##H means un-altered fuelling.

,f 5ou are upgrading from a previous firmare version* to change 5ou settings to the current method!

a. asic/Coad Settings - &arometric correction is t5picall5 all 0##H ith small adAustments up or don as

required.

&. Tools - ;ali&rate M<(/&aro

1<t total vacuum1 Q #

1Bate1 Q #.

ou must perform steps a <+ &. See also the tooltips GU on those pages.

3. <ir-densit5

,n previous versions* there as an internal calculation for air densit5 ith a tea8 curve on top.

The ne method exclusivel5 uses the adAustment curve. 0##H means un-altered fuelling.

ote! M<T does change air densit5 and the speed-densit5 equation relies on this to estimate inta8e charge.

4. Spar8 output polarit5

The name has &een simplified

1oing Digh1 - as called 1oing Digh ),nverted1

1oing Co1 - as called 1oing Co )ormal1

+@6CE ;DE; @6B SETT, E9@BE ;@E;T, ;@,CS.

$. oost ;ontrol

To ma8e things more intuitive e have no changed the firmare so that

- 1ormal1 is the most t5pical output polarit5 setting

- larger &oost dut5H num&ers mean more &oost.

,f 5ou are upgrading from a previous firmare version* then the oost @utput polarit5 setting ill &e theopposite. 9or most users it ill no &e 1ormal1.

This is true hether using open- or closed-loop &oost control.

,f 5ou are using closed-loop* 5ou ill need to retune 5our (,+ settings and alter the sensitivit5 slider asrequired.

@pen loop &oost users most li8el5 need to set their ta&le so that!

nePcellPvalue Q 0## - oldPcellPvalue

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Bemem&ering that more dut5 Q more &oost.

=. Serial protocol

The firmare no uses the 1neserial1 protocol shared ith MS3. This requires compati&le tuning softareand firmare loaders.

)ote* it 5ou ant to revert to an older firmare version 5ou ill need to use

the ne firmare loader* or use the &oot Aumper.

%. Microsquirt CE+ spar8 output!

hen used as a single coil* the polarit5 of the output no &ehaves the same

as MS3 such that Fgoing highF means the output is high during the dell period.

+@6CE ;DE; @6B SETT, E9@BE ;@E;T, ;@,CS.

>. ,dle control options.

,f 5ou are upgrading from a previous firmare version* 5ou need to verif5!

-valve t5pe

-open/closed loop

-output port

,f 5ou are using closed-loop* 5ou ill need to retune 5our (,+ settings and

alter the sensitivit5 slider as required.

?. Bev limiter settings.

The configuration and &ehaviour of the rev limiters has changed.

"erif5 limiter t5pes and rev limits

0#. ;< expansion!

6pgrade users ill need to verif5!

-all settings

-remote port settings for flex* 8noc8* nitrous* idle* ta&le-sitching

00. Botar5 ignition!


-all settings

02. ,dle <dvance!


-all settings

03. ,nAector deadtime/(M!


-(M on/off setting

04. 6nused settings no removed ill give harmless arnings!

(ort inAection

<M;option

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feature4P#maxdl* mindl* vanos

@ld test mode settings

0$. M 5pass polarit5 might &e rong if 5ou use S0# for spar8 output.

0=. Most ta&les no sho true units on the load axis instead of 1H1

This ill cause man5 arnings hen loading an old MS7. The values ill

transfer over o8.

0%. To TunerStudio dash indicators have &een renamed!

8ot Synced - 8ot RPM Synced

+a%f-sync - +a%f-RPM sync

ou ill need to re-load 5ou dash )right-clic8 on a &lan8 area of the dash select Coad/Save* then Coaddash&oard* then <ccept or update manuall5.

0>. Some 1trigger heel1 users ma5 need to change their toothX0 angle if it as close to 3=#deg or %2#deg.)< previous &ug as fixed.

0." %'radin' *rom 3.!.5 or 3.1.5

ou can mostl5 load 5our MS2/Extra 3.#.x or 3.0.x tune into MS2/Extra 3.3.x

See the notes in section <.3

0.0 %'radin' *rom 2.1.!

ou can mostl5 load 5our MS2/Extra 2.0.# tune into MS2/Extra 3.3.x

Fey differences

Sequential fuel supported )ith hardare mods.

<ccel enrichment T(Sdot values 0#x larger.

e sure to alter these values in the <cceleration iLard. @pen up the values ta&le for the T(S &ased <Ecurve and multipl5 all values in the rateH column &5 0#. 9ind T(Sdot threshold and multipl5 that &5 0#.

These are the default settings!

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The ( adder values ill need to &e tuned to suit 5our inAector siLe and engine &ehaviour.

See also the notes in section <.3

0.# %'radin' *rom MS2@(

,o not try to %oad your o%d MS2/! 12.GH0 etc. settings.

,f 5our fuel and spar8 ta&le are ell tuned* then retain them. @therise start from scratch as if a ne user.

9ollo the steps in <.% to export and import 5our ta&les.

<lthough the MS2/Extra code evolved from an earl5 MS2/ code* man5 settings are somehat differentand man5 ne features exist.

Fey differences

,gnition mode selection is direct* chose 5ou tach input source.

;hec8 5our spar8 output: S0# is standard on MS2/* +04 is standard on MS2/Extra

The regular heel decoder requires a single 1Tooth X0 angle1 instead of s8ip teeth etc. ,t automaticall5calculates the triggers itself and ena&les the required num&er of spar8 outputs depending on ho man5c5linders 5ou have and 5our selection of single coil* asted spar8* coil-on-plug or dual-diLL5.

(M idle valve duties or8 so that #H means full5 closed.

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Stepper idle valves or8 so that # steps is full5 closed.

<n alternate all-etting transient method 1E<E1 is availa&le.

Bev limiting is changed

Carger fuel and spar8 ta&les.

Man5 ne features.

ote that if 5our Megasquirt is alread5 ired up and or8ing ith MS2/ code then 5ou should not need tochange an5 of that iring hen moving to MS2/Extra - carefull5 revie 5our settings for input capture andspar8 output polarit5 and &ring them across.

0. %'radin' *rom MS1@E5tra

,o not try to %oad your o%d MS'E)tra 1a%so referred to as Megasquirtnspar or MSnE,IS settingsinto Megasquirt-2.

,f 5our fuel and spar8 ta&le are ell tuned* then retain them. @therise start from scratch as if a ne user.

9ollo the steps a&ove in <.% to export and import 5our ta&les.

Fey differences

<lmost all other settings are somehat different &eteen MS0/Extra and Megasquirt-2.

The heel decoder no requires a single 1Tooth X0 angle1 and automaticall5 calculates the triggers itself andena&les the required num&er of spar8 outputs depending on ho man5 c5linders 5ou have and 5ourselection of single coil* asted spar8* coil-on-plug or dual-diLL5.

Spar8 <**; are availa&le on the CE+s )not 9,+CE

Spar8s +*E*9 have moved

Caunch pins are different

itrous pins are different and the iring method has changed

ater inAection is not supported

3 stage shift lights not supported

Spare <+;s the same.

02" poer feed to the chip to ena&le the stepper driver );aution: +o not refit the Megasquirt-0 ;(6 ith the02" feed in place.

hether 5ou imported a "E ta&le or not* 5ou no must go through all settings to configure for 5our engine.e.g. num&er of c5linders* Beq9uel* ignition triggering* spar8 and fuel hardare in use.

0.9 %'radin' *rom MS1 +ase,,o not try to %oad your o%d Megasquirt-' settings into Megasquirt-2.

,f 5our fuel "E ta&le is ell tuned* then retain it. @therise start from scratch )online as if a ne user.

To transfer 5ou "E ta&le

@pen up 5our tuning softare and load 5our Megasquirt-0 tune.

@pen the "E ta&le. Export as "EN.

;lose tuning softare.

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Megasquirt-2 Setting 6p %!<ppendix ! 9uel calculations

: 6ppendi) /: 4ue% ca%cu%ationsThere are a num&er of different methods to estimate the airflo into an engine. This page ill explain hothe fuel is mathematicall5 calulated using each method.

#.1 /erms sed

See also the lossar5 for general E9, related a&&reviations.

P5 - &ase fuel pulseidth &efore per-c5linder trims etc.

,$ - inAector dead-time )opening time less closing time

Req4ue% - the glo&al fuel constant

E - the F"EF ta&le. @ften expressed as "EB(M*M<(U meaning that this loo8up ta&le is &ased on B(M andM<( in the axes.

6ir,en - air densit5 correction )centred on 0##H calculated from the M<T sensor reading.

/aroCor - &arometric correction )centred on 0##H calculated from the intial M<( reading or dedicatedsensor corrections - other adAustments such as armup enrichment* closed loop E@* acceleration

#.2 S%eed Bensit&

The primar5 load input is the M<( sensor.

ith FMultipl5 M<(F* ithout F,nclude <9B targetF

P5 J ,$ K 1Req4ue% L M6P L ERPM;M6PN L 6ir,en L /aroCor L corrections

ith FMultipl5 M<(F* ith F,nclude <9B targetF

P5 J ,$ K 1Req4ue% L M6P L Stoic&64Rtarget L ERPM;M6PN L 6ir,en L /aroCor L corrections

#.3 (.2 -l%ha$ +%ure,

The primar5 load input is the throttle* this is often a poor indicator.

ithout FMultipl5 M<(F* ithout F,nclude <9B targetF

P5 J ,$ K 1Req4ue% L ERPM;$PSN L 6ir,en L /aroCor L corrections

ithout FMultipl5 M<(F* ith F,nclude <9B targetF

P5 J ,$ K 1Req4ue% L Stoic&64Rtarget L ERPM;$PSN L 6ir,en L /aroCor L corrections

#.4 -l%ha$ +h&rid,

The primar5 load input is the throttle* &ut M<( is also included in the calculation.

ith FMultipl5 M<(F* ithout F,nclude <9B targetF

P5 J ,$ K 1Req4ue% L M6P L ERPM;$PSN L 6ir,en L /aroCor L corrections

ith FMultipl5 M<(F* ith F,nclude <9B targetF

P5 J ,$ K 1Req4ue% L M6P L Stoic&64Rtarget L ERPM;$PSN L 6ir,en L /aroCor L corrections

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Megasquirt-2 Setting 6p >!<ppendix ;! Megasquirt lossar5 of Terms

G: 6ppendi) C: Megasquirt !%ossary of $er#s6,C W stands for 1analog-to-digital converter1. ,n this case* it is part of the conversion circuitr5 in the ;(6that translates the var5ing voltage signal to a digital value that the ;(6 can understand and operate on. <ll

of the sensors )T(S* M<(* ;CT* M<T send their signal to a particular <+; pin on the processor. The <+;result is used &5 the processor as a FcountF. MS-, has an eight &it <+;* so the counts can &e from # to 2$$.MS2 and MS3 have a more precise 0#-&it <+;* so the count can &e from #-0#23. oth of these are mappedover a #-$ "olt range )so the voltage into the <+; Q <+; count V $.#/0#23 for MS2* for example' hoever*higher external voltage ma5 &e &rought don to a #-$ volt range ith a voltage divider or &oosted ith anamplifier )such as for ETs.

6E W <cceleration Enrichment* the enriched mixture provided hen the throttle position sensor signal)T(Sdot or map sensor signal )M<(dot changes at various rates.

64M 6ir 4%o( #eter. @ften a vane or flapper t5pe device used to measure air-flo into an engine.

64R W <ir 9uel Batio* the mass ratio of air to fuel in the com&ustion cham&er. See lam&da* - and -E@ sensors* &elo.

6%p&a-8 W 9uelling algorithm that uses throttle position as the primar5 load. Should not &e used ontur&ocharged engines.

6SE W <fter Start Enrichment* the enriched mixture provided for a num&er of engine c5cles hen MegaSquirtdetects that the engine has transitioned from cran8ing to running.

6MC W <utomatic Mixture ;ontrol* a control s5stem availa&le in MS2/ code to automaticall5 tune fuel ithin the E;6 using feed&ac8 from the ox5gen sensor ithout use of a laptop. Should &e used ith greatcaution as a defective @2 sensor could cause a good "E ta&le to &e iped out.

6$,C W <fter Top +ead ;enter* the cran8shaft position ith respect to the piston &eing at the top of its travel*meaning it has passed itFs highest position and is descending.

/aro W arometer - the am&ient air pressure. <t sea level this is around 0##8(a. <t high elevations it ma5 &e>#8(a. The fuelling needs to ta8e account of this.

="aro W a fuelling algorithm here engine load Q M<(/aro and the speed-densit5 s5stem is used. Thisalters hat values are loo8ed up in the fuel "E ta&le.

/aro#etric correction W a calculation that alters fuelling &ased on the am&ient air pressure. ,mportant atvar5ing elevations. @f little importance in lo-l5ing countries.

/IP W a ro&ust ignition driver transistor from osch. 9eatures over-currrent and over-temperatureprotection. 6sed in all good Megasquirt 8its. eare of lesser alternatives.

/$,C W efore Top +ead ;enter* the cran8shaft position ith respect to the piston &eing at the top of itstravel* meaning it has @T passed itFs highest position and is rising. Most normal spar8 event occur T+;.

C68 W );ontroller <rea etor8 - a dedicated automotive netor8ing s5stem to allo different automotiveprocessors to communicate and share inputs and calculated results. 6sed as a convenient a5 to extend the

inputs and outputs of the Megasquirt E;6. )ot availa&le on Megasquirt-0

Car"on Mono)ide 1C W (oisonous gas produced during com&ustion process. ,n an automotive context*generall5 refers to regulated car&on monoxide );@ tail pipe emissions.

C6S W ;ran8 <ngle Sensor. @ften used to refer to com&ined cran8 and cam position sensors mounted herehistoricall5 a distri&utor ould have &een.

Cata%ytic con*erter W a chemical device in the vehicleFs exhaust s5stem that can reduce the amount ofregulated emissions emitted &5 converting ox to 2 R #2* ;@ to ;@2 and D; to ;@2 R D2#. ;atal5ticmeans the converter active su&strate facilitates the reactions* &ut is not consumed )and thus has a long life ith no replenishment requirements.

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CI, W ;u&ic ,nch +isplacement. The imperial measure of the sept volume of the pistons. =0.#2 cu&icinches Q 0 litre.

C%osed %oop W refers to those times hen an E9, computer is using feed&ac8 from a sensor to alter outputs

C%osed %oop "oost W Megasquirt uses a (,+ to 8eep &oost in line ith a &oost target ta&le

C%osed %oop E! W Megasquirt controls the E@ to the target ta&le &5 var5ing the inAected fuel amounts.

C%osed %oop id%e W Megasquirt controls the idle rpm &5 opening or closing the idle valve as required.

C+$ W ;5linder Dead Temperature* used instead of coolant temperature );CT on air-cooled engines.

CFP W ;ran8shaft position sensor

C>$ W ;oolant Temperature sensor )a8a. ;TS. 6suall5 the ;CT sensor is an T; )egative Temperature;oefficient thermistor* or a resistor hose resistance varies ith temperature )T; means the resistancegoes don as the temperature goes up.

CMP W ;amshaft position sensor

C8P W ;oil ear (lug W See ;oil on (lug

Coi% n P%ug W @ne ignition coil is installed per spar8 plug. Either directl5 on top of the plug e.g.* a FpencilFcoil. @r in close proximit5 ith a short plug-lead )actuall5 coil near plug. This setup can give maximum spar8energ5 and can &e the neatest install ith least lost spar8 energ5.

CP W ;oil on (lug W See ;oil on (lug

CPS W (ossi&l5 am&iguous ;ran8shaft or camshaft position sensor

CPU W ;entral (rocessing 6nit* a8a. 1processor1 or 1microprocessor1 the computational engine that performsthe calculations to operate the inAection and ignition functions in MegaSquirt]. ,t has a num&er of supportcircuits* li8e the poer circuit* the cloc8 circuit* the serial and ;< communications circuits* and various inputand output conditioning circuits.

C$S W ;oolant Temperature Sensor )a8a. ;CT. 6suall5 the ;TS is an T; )egative Temperature;oefficient thermistor* or a resistor hose resistance varies ith temperature )T; means the resistance

goes don as the temperature goes up.

,iode W < to lead electrical device that allos current to flo in onl5 one direction )see also [ener diodes.

,I W +o-,t-ourself.

,MM W )digital multi meter electronic current/resistance/potential measuring tool. )Bequired tool for an5Megasquirt install. Ma5 also &e referred to as +"M )digital volt meter.

,ua% ta"%e W < firmare feature alloing different inAector outputs to have independent fuel ta&les. ;an &eused as an a8ard method to achieve per-&an8 trim. More commonl5 used )ith external rela5s to map forregular fuel and C(.

,uty Cyc%e W )+;W < num&er indicating the amount of time that some signal is at full poer. ,n the contextof MegaSquirt E9, ;ontroller* dut5 c5cle is used to descri&e the amount of time that the inAectors are on* and

to descri&e the JholdK part of the pea8 and hold inAector drivers )see Co ,mpedance ,nAectors* &elo.ECU W )Electronic ;ontrol 6nit is the general term for a fuel inAection controller* of hich MegaSquirt is anexample.

E,IS W Electronic +istri&utorless ,gnition S5stem is 9ordFs asted-spar8 computer-controlled ignition module* hich has a simple to ire hoo8up to MegaSquirt for full mapped ignition control.

E! Sensor W Exhaust as @x5gen sensor* used to descri&e the sensor in the exhaust that measures thelean/rich state of the inta8e mixture. 6sed to control the fuel via a feed&ac8 algorithm called Jclosed loopK.

E!R W Exhaust as Becirculation. 6sed &5 @EMs for emissions purposes. ot supported &5 Megasquirt.

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5our target <9Bs. Then the "E ta&le is tuned to achieve that <9B. Turning the setting on/off ill require acomplete re-tune.

Interpo%ate W The dictionar5 meaning is to insert an intermediate value into a series &5 estimating orcalculating it from surrounding 8non values. @n all ta&les and curves* hen 5ou are &eteen points* theMegasquirt interpolates the intermediate values. Some older other &rands ere una&le to do this and

required monstrousl5 large ta&les to overcome this limitation.

Pa 1i%oPasca%s W the measurement of air pressure used in MegaSquirt] computations. ,t ranges from #)vacuum to 0#0.3 8(a )standard atmospheric pressure at sea level to 2$# 8(a )20psi of &oost or higher.

>a#"da W an alternative term to <9B here 0.# is stoichiometric. Cam&da num&ering is fuel independent.0.# is ala5s stoich.

>o( I#pedance In@ectors W )a.8.a lo-[* lo ohm 9uel inAectors that are designed to run at a much loercurrent than ould &e supplied &5 a direct 02 volt connection. The5 require a special signal that is initiall5 atfull current )4-= amps* a.8.a. Jpea8 currentK for a&out 0.#-0.$ ms* &ut then drops don to a&out 0 amp )JholdcurrentK for the rest of the opening pulse. The resistance of a lo-impedance inAector is t5picall5 0-3 ohms.These ma5 need a 1pea8 and hold1 &oard or a resistor pac8.

>SU-A W osch ide-&and ox5gen sensor.

M64 sensor W Mass <ir 9lo sensor. < sensor used to measure the mass of air flo through the inta8e tract)hich must &e sealed at the senor and donstream.

M6P sensor W Manifold <&solute (ressure sensor. Measure of the a&solute pressure in the inta8e manifold)related to the engine vacuum* to determine the load on the engine and the consequent fuelingrequirements. The standard M<( sensor in MegaSquirt] is the M(N42$# )2.$# <B* or 0$ psi )vacuum R20 psig )&oost. < &asis of the 1speed densit51 fuelling algorithm.

M6Pdot W rate of change of M<( value. )dM<(/dt 6sed mainl5 to trigger <ccel enrichment.

M6$ Sensor W Manifold <ir Temperature sensor* the same as ,<T. The M<T circuit is identical to the ;CTcircuit* see ;CT* a&ove.

.MS> W file extension used &5 the MegaSquirt for storing datalogs ).NCS might also &e used for datalogs ith

older versions of tuning softare.

MPA2<06P W the standard internal M<( sensor used in MegaSquirt.

MS W MegaSquirt* used in this document to refer to the MegaSquirt] fuel inAection controller or its em&eddedsoftare. e.g.* MS0 Q Megasquirt-0* MS2 Q Megasquirt-2* MS3 Q Megasquirt-3

MS'E)tra W The most commonl5 used firmare on the Megasquirt-0 chip. ives fuel and spar8 control.6sed to &e called MegasquirtFnFspar8-extra or MSnS-extra. The original &asic MS0 code as fuel onl5.

MS2E)tra W 9irmare for the MS2 chip and Microsquirt ith multiple spar8 outputs* man5 heel decoders*closed loop idle* &oost* nitrous* ta&le sitching and more

MS2/! W More &asic firmare for the MS2 chip and Microsquirt from oling and rippo.

.MSQ W file extension used for saving MegaSquirt fuel inAection controller user settings )a8a. 1parameters1

on a tuning computer. Since approximatel5 2##$* these have &een reada&le NMC format* so 5ou can openthese in otepad or similar text editors. This format allos some exchange of tune data &eteen differentcode versions.

8/-E! Sensor W arro and E@ sensor* gives a sitch at the stoichiometric ratio )the chemicall5correct mixture of air and fuel* &ut unrelia&le for <9B other than stoichiometric.

&#s >a( W < fundamental la of electricit5* that states that the current flo ), is equal to the voltage )"divided &5 the resistance )B* or!

, Q "/B

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)ides of 8itrogen 18) W in an automotive context* generall5 refers to regulated Fmono-nitrogen oxidesF)@ and @2 tail pipe emissions.

EM W )original equipment manufacturer - refers to parts produced for initial assem&l5 of a ne vehicle. )<sopposed to after mar8et parts.

pen >oop W refers to those times hen MegaSquirt or8s entirel5 from its calculations ith no feed&ac8from a sensor )compare ;losed Coop.

pen >oop /oost W there is no feed&ac8 from the map sensor W &oost dut5 is controlled &5 the dut5 ta&leonl5.

pen >oop E! W there is no feed&ac8 from the ox5gen sensor W fuelling is from the "E ta&le onl5.

pen >oop Id%e W there is no feed&ac8 loop ith rpm W idle valve position is set onl5 from the ta&le.

PC/ W )printed circuit &oard W the fi&erglass &oard that has the MegaSquirt component la5out and circuitsimprinted on it.

PI, W )(roportional* ,ntegral* +erivative - a method of closed-loop feed&ac8 control

Pu%%-up Circuit W < ver5 simple circuit consisting of a voltage suppl5 and a current limiting resistor designed

to prevent a signal from floating* it forces the signal to either &e high )equal to the pull up voltage or lo)grounded.

PT+ In@ectors W (ea8 and hold inAectors' see Co ,mpedance inAectors.

PIP W (rofile ,gnition (ic8-up is the term used for the signal sent from 9ordFs Electronic +istri&utorless,gnition S5stem )E+,S to the electronic control unit. The E+,S module decodes the 3=-0 heel and sends 2*3 or 4 (,( pulses per engine revolution depending on E+,S4*=*>. The (,( signal into the E;6 is a square ave sitched at 02 volts. ,t provides information a&out &oth the engine speed and position.

P5 W )(ulse idth is the amount of time a signal is applied during each period. 9or example* is the amountof time )in milliseconds an inAector is pulled lo )grounded to inAect fuel.

Pu%se 5idt& Modu%ation 1P5M W < signal ith a fixed pulse idth )frequenc5* hich is turned on for partof the pulse. The percent of time that the signal is on is called its dut5 c5cle. (M is used to limit current to

lo impedance fuel inAectors* as ell as for solenoids such as idle valves* &oost solenoids and ""T

Rea%ti#e "aro W a dedicated second pressure sensor is used to monitor am&ient pressure. Bequired if 5ourvehicle ill go on Aourne5s at var5ing elevations.

Required 4ue% W )BeqP9uel The inAector pulse idth* in milliseconds* required to suppl5 the fuel for a singleinAection event at stoichiometric com&ustion* 0##H volumetric efficienc5 and standard temperature.

RPM W Bevs (er Minute. The term used to descri&e engine speed.

S65 W Spar8 <dvance ord is the FreturningF signal to a 9ord E+,S ignition unit from the E;6 that sets theamount of ignition advance requested. ,t is in the form of a $ volt square ave.

Se#i-sequentia% W 9uelling s5stem here inAection events are timed to each c5linder )li8e spar8 is &ut occurtice per c5cle. @ffers some of the &enefits of full sequential ithout needing a cam heel input.

14u%%y Sequentia% W 9uelling s5stem here inAection events are timed to each c5linder )li8e spar8 is andoccur once per c5cle. +o not confuse ith direct inAection. Sequential uses normal inAectors of a normal siLe*&ut their timing can give slight poer and/or econom5 increases

Sti# 1MegaSti#u%ator W the original stimulator is a small &oard hich plugs into the connector of theMegaSquirt] controller. ,t simulates all the sensor the inputs the MegaSquirt] controller ould normall5 see)&ut the rpm signal is onl5 suita&le for use ith distri&utor or E+,S configurations and provides poer to theMegaSquirt] controller. The Stimulator also allos 5ou to monitor the MegaSquirt] controllerFs inAectionpulses actualU* fuel pump rela5 operation* and fast idle solenoid output ith four CE+s. The imStim is anenhanced version that simulates man5 heel patterns and has more CE+s for multiple spar8 outputs.

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/H2' W a particular ,T designed for use ith automotive ignition coils. o superceded &5 ,(3%3.

E W "olumetric Efficienc5. The actual amount of air &eing pumped &5 the engine as compared to itstheoretical maximum. < 2### cc engine ill theoreticall5 move 2### cc of air in one c5cle at 0##H efficienc5.,f the engine is actuall5 running at %$H "E* then it ill move 0$## cc of air on each c5cle.

ref W a $ "olt suppl5 used to poer the T(S )and sometimes other external components needing a $ "oltsuppl5* li8e ignition modules or pull-ups.

R sensor - "aria&le reluctor sensor W is an induction t5pe sensor* it is 1passive1* i.e.* it does not require apoer source* and has a small magnet &uilt in. eeds to use a conditioning circuit W as provided on the "3.#and "3.$% main&oard. ;annot &e used directl5 on the "2.2 main&oard.

5asted-CP W a method here individual coils are fitted per spar8 plug* &ut the coils are fired in a FastedFmanner tice per c5cle. This is used during startup in some heel modes and could also &e usedtemporaril5 &5 a user &efore full coil-on-plug is installed.

5asted Spar W < method of firing spar8 plugs in hich one Fdou&le-endedF coil simultaneousl5 fires tocoils on different c5linders. @ne of the c5linders is the intended FtargetF* and is near T+; on its compressionstro8e* the other c5linder is offset &5 3=#Z in the firing order )of the %2#Z 4-stro8e c5cle* so it is near T+; onits exhaust stro8e. The second spar8 is said to &e FastedF &ecause it does not ignite a mixture. @n the otherhand* the hot ioniLed exhaust gases require little energ5 to create a spar8* so nearl5 all the energ5 goes tothe FtargetF c5linder. <n example of a asted spar8 s5stem is 9ordFs E+,S. The advantage is that hile amissing tooth cran8 heel is required* no cam s5nc signal )and the corresponding heel and sensor areneeded.

5/-E! Sensor W ide and E@ sensor* can &e used to derive real <9B data ith mixtures from 0#!0 to2#!0* i.e.* an5thing 5ou are li8el5 to &e interested in. <llos for lean or rich tuning.

5$ W ide open throttle.

5UE W arm 6p Enrichment* the enriched mixture applied hen the coolant temperature is lo.

ener diode W < diode that allos current to flo in one direction* unless the reverse voltage is higher thanits rated avalanche voltage* in hich case it ill flo in the reverse direction. @ften used to limit excessivevoltage to certain circuits &5 shunting it either to ground or the poer suppl5.

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Megasquirt-2 Setting 6p ?!Bevision histor5

H: Re*ision &istory

2#04-#%-22 Bevision histor5 started

2#04-#%-23 <dded ""T section 4.?

2#04-#>-3# <dded serial trou&leshooting section. Ena&led auto num&ering.

2#04-#?-#% <dded note a&out resistor plugs.

2#0$-#2-#2 ,dle homing steps setup procedure. Cinux group note. lossar5 from MS3. ;< configfrom MS3. custom.ini. <ppl5 similar edits from FCaminarF. Minor staging t5po.

2#0$-#%-0# <dd in versions section from MS3. ump rev to 3.4

megasquirt2 setting up-3.4

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