ignition system - ertyu.org system table of contents ... voltage switches from low (metal) to high...

D

R

D

I

D

pt

O

Pasi

S

st

bcilt

aS

PL IGNITION SYSTEM 8D - 1

IGNITION SYSTEM

TABLE OF CONTENTS

page page

ESCRIPTION AND OPERATIONIGNITION SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . 1SPARK PLUGS . . . . . . . . . . . . . . . . . . . . . . . . . . . 1SPARK PLUG CABLES . . . . . . . . . . . . . . . . . . . . . 1ELECTRONIC IGNITION COILS. . . . . . . . . . . . . . . 2AUTOMATIC SHUTDOWN RELAY. . . . . . . . . . . . . 2CRANKSHAFT POSITION SENSOR—PCM

INPUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3CAMSHAFT POSITION SENSOR—PCM

INPUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4KNOCK SENSOR. . . . . . . . . . . . . . . . . . . . . . . . . . 5IGNITION SWITCH . . . . . . . . . . . . . . . . . . . . . . . . 5LOCK KEY CYLINDER. . . . . . . . . . . . . . . . . . . . . . 5IGNITION INTERLOCK . . . . . . . . . . . . . . . . . . . . . 6EMOVAL AND INSTALLATION
SPARK PLUG SERVICE . . . . . . . . . . . . . . . . . . . . 6
SPARK PLUG CABLE SERVICE . . . . . . . . . . . . . . 6IGNITION COIL . . . . . . . . . . . . . . . . . . . . . . . . . . . 6AUTOMATIC SHUTDOWN RELAY. . . . . . . . . . . . . 6CAMSHAFT POSITION SENSOR. . . . . . . . . . . . . . 6CRANKSHAFT POSITION SENSOR. . . . . . . . . . . . 8KNOCK SENSOR. . . . . . . . . . . . . . . . . . . . . . . . . . 8IGNITION SWITCH . . . . . . . . . . . . . . . . . . . . . . . . 8LOCK KEY CYLINDER. . . . . . . . . . . . . . . . . . . . . . 9IGNITION INTERLOCK . . . . . . . . . . . . . . . . . . . . 10

SPECIFICATIONSVECI LABEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10FIRING ORDER—2.0L . . . . . . . . . . . . . . . . . . . . 10TORQUE SPECIFICATION . . . . . . . . . . . . . . . . . . 11SPARK PLUG CABLE RESISTANCE—SOHC. . . . 11SPARK PLUG . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
IGNITION COIL . . . . . . . . . . . . . . . . . . . . . . . . . . 11
ESCRIPTION AND OPERATION

GNITION SYSTEM

ESCRIPTIONThe system’s three main components are the coil

ack, crankshaft position sensor, and camshaft posi-ion sensor.

PERATIONBasic ignition timing is not adjustable. The

owertrain Control Module (PCM) determines sparkdvance. The 2.0L engines use a fixed ignition timingystem. The distributorless electronic ignition systems referred to as the Direct Ignition System (DIS).

PARK PLUGSThe 2.0L engines uses resistor spark plugs. For

park plug identification and specifications, Refer tohe Specifications section at the end of this group.

Remove the spark plugs and examine them forurned electrodes and fouled, cracked or broken por-elain insulators. Keep plugs arranged in the ordern which they were removed from the engine. An iso-ated plug displaying an abnormal condition indicateshat a problem exists in the corresponding cylinder.

Spark plugs that have low mileage may be cleanednd reused if not otherwise defective. Refer to thepark Plug Condition section of this group. After

cleaning, file the center electrode flat with a smallpoint file or jewelers file. Adjust the gap between theelectrodes (Fig. 1) to the dimensions specified in thechart at the end of this section by bending theground electrode (just above the attachment weld)with the appropriate tool.

Never apply any force between the electrode ordamage to the center electrode assembly will result.

Always tighten spark plugs to the specified torque.Over tightening can cause distortion and damage.Tighten spark plugs to 28 N·m (20 ft. lbs.) torque.

SPARK PLUG CABLESSpark plug cables are sometimes referred to as sec-

ondary ignition wires. The wires transfer electricalcurrent from the coil pack to individual spark plugsat each cylinder. The resistor type, nonmetallic sparkplug cables provide suppression of radio frequencyemissions from the ignition system.

Check the spark plug cable connections for goodcontact at the coil and spark plugs. Terminals shouldbe fully seated. The nipples and spark plug coversshould be in good condition. Nipples should fit tightlyon the coil. Spark plug boot should completely coverthe spark plug hole in the cylinder head cover. Installthe boot until the terminal snaps over the sparkplug. A snap must be felt to ensure the spark plugcable terminal engaged the spark plug.

tTPfms

E

D

T

O

WESW

cstnfo

vgtp

8D - 2 IGNITION SYSTEM PL

DESCRIPTION AND OPERATION (Continued)

Loose cable connections will corrode, increase resis-ance and permit water to enter the coil towers.hese conditions can cause ignition malfunction.lastic clips in various locations protect the cables

rom damage. When the cables are replaced the clipsust be used to prevent damage to the cables, and

hould be rotated about 30° below the horizontal.

LECTRONIC IGNITION COILS

ESCRIPTIONThe coil pack consists of 2 coils molded together.

he coil pack is mounted on the valve cover (Fig. 2).

PERATION

ARNING: THE DIRECT IGNITION SYSTEM GEN-RATES APPROXIMATELY 40,000 VOLTS. PER-ONAL INJURY COULD RESULT FROM CONTACTITH THIS SYSTEM.

High tension leads route to each cylinder from theoil. The coil fires two spark plugs every powertroke. One plug is the cylinder under compression,he other cylinder fires on the exhaust stroke. Coilumber one fires cylinders 1 and 4. Coil number twoires cylinders 2 and 3. The PCM determines whichf the coils to charge and fire at the correct time.The Auto Shutdown (ASD) relay provides battery

oltage to the ignition coil. The PCM provides around contact (circuit) for energizing the coil. Whenhe PCM breaks the contact, the energy in the coilrimary transfers to the secondary causing the

Fig. 1 Checking Spark Plug Electrode Gap1 – TAPER GAUGE
spark. The PCM will de-energize the ASD relay if it
does not receive the crankshaft position sensor andcamshaft position sensor inputs. Refer to Auto Shut-down (ASD) Relay—PCM Output, in this section forrelay operation.

AUTOMATIC SHUTDOWN RELAY

DESCRIPTIONThe ASD relay is located in the PDC (Fig. 3). The

inside top of the PDC cover has label showing relayand fuse identification.

Fig. 2 Ignition Coil Pack1 – IGNITION COILS2 – SPARK PLUG CABLE3 – SPARK PLUG INSULATOR

Fig. 3 Power Distribution Center (PDC)

O

tc

soflc

goitcddcsA

CI

D

ef

c



PERATIONThe Automatic Shutdown (ASD) relay supplies bat-

ery voltage to the fuel injectors, electronic ignitionoil and the heating elements in the oxygen sensors.A buss bar in the Power Distribution Center (PDC)

upplies voltage to the solenoid side and contact sidef the relay. The fuse also protects the power circuitor the fuel pump relay and pump. The fuse isocated in the PDC. Refer to the Wiring Diagrams forircuit information.The PCM controls the ASD relay by switching the

round path for the solenoid side of the relay on andff. The PCM turns the ground path off when thegnition switch is in the Off position. When the igni-ion switch is in On or Start, the PCM monitors therankshaft and camshaft position sensor signals toetermine engine speed and ignition timing (coilwell). If the PCM does not receive crankshaft andamshaft position sensor signals when the ignitionwitch is in the Run position, it will de-energize theSD relay.

RANKSHAFT POSITION SENSOR—PCMNPUT

ESCRIPTIONThe crankshaft position sensor mounts to the

ngine block behind the generator, just above the oililter (Fig. 4).

The PCM uses the Crankshaft Position sensor toalculate the following:• Engine RPM

Fig. 5 Timing Re1 – MACHINED NOTCHES2 – CRANKSHAFT POSITION SENSOR

• TDC number 1 and 4• Ignition coil synchronization• Injector synchronization• Camshaft-to-crankshaft misalignment (Timing

belt skipped 1 tooth or more diagnostic trouble code).

OPERATIONThe Crankshaft Position (CKP) sensor is a Hall-ef-

fect sensor. The second crankshaft counterweight hastwo sets of four timing reference notches including a60 degree signature notch (Fig. 5).

nce Notches

Fig. 4 Crankshaft Position Sensor1 – CRANKSHAFT POSITION SENSOR2 – OIL FILTER3 – GENERATOR

fere

eHAs5

tacgwgvt

woeasolet

flt6ons(

itndtcltd



The PCM sends approximately 8 volts to the Hall-ffect sensor. This voltage is required to operate theall-effect chip and the electronics inside the sensor.ground for the sensor is provided through the sen-

or return circuit. The input to the PCM occurs on avolt output reference circuit.The notches generate pulses from high to low in

he crankshaft position sensor output voltage. Whenmetal portion of the counterweight aligns with the

rankshaft position sensor, the sensor output voltageoes low (less than 0.5 volts). When a notch alignsith the sensor, voltage goes high (5.0 volts). As aroup of notches pass under the sensor, the outputoltage switches from low (metal) to high (notch)hen back to low.

If available, an oscilloscope can display the squareave patterns of each voltage pulses. From the widthf the output voltage pulses, the PCM calculatesngine speed. The width of the pulses represent themount of time the output voltage stays high beforewitching back to low. The period of time the sensorutput voltage stays high before switching back toow is referred to as pulse width. The faster thengine is operating, the smaller the pulse width onhe oscilloscope.

By counting the pulses and referencing the pulserom the 60 degree signature notch, the PCM calcu-ates crankshaft angle (position). In each group ofiming reference notches, the first notch represents9 degrees before top dead center (BTDC). The sec-nd notch represents 49 degrees BTDC. The thirdotch represents 29 degrees. The last notch in eachet represents 9 degrees before top dead centerTDC).

The timing reference notches are machined at 20°ncrements. From the voltage pulse width the PCMells the difference between the timing referenceotches and the 60 degree signature notch. The 60egree signature notch produces a longer pulse widthhan the smaller timing reference notches. If theamshaft position sensor input switches from high toow when the 60 degree signature notch passes underhe crankshaft position sensor, the PCM knows cylin-er number one is the next cylinder at TDC.

CAMSHAFT POSITION SENSOR—PCM INPUT

DESCRIPTIONThe camshaft position sensor attaches to the rear

of the cylinder head. The PCM determines fuel injec-tion synchronization and cylinder identification frominputs provided by the camshaft position sensor (Fig.6) and crankshaft position sensor. From the twoinputs, the PCM determines crankshaft position.

OPERATIONThe PCM sends approximately 8 volts to the hall

affect sensor. This voltage is required to operate thehall effect chip and the electronics inside the sensor.A ground for the sensor is provided through the sen-sor return circuit. The input to the PCM occurs on a5 volt output reference circuit.

A target magnet attaches to the rear of the cam-shaft and indexes to the correct position. The targetmagnet has four different poles arranged in an asym-metrical pattern (Fig. 7). As the target magnetrotates, the camshaft position sensor senses thechange in polarity (Fig. 8). The sensor output switchswitches from high (5.0 volts) to low (0.5 volts) as thetarget magnet rotates. When the north pole of thetarget magnet passes under the sensor, the outputswitches high. The sensor output switches low whenthe south pole of the target magnet passes under-neath.

The sensor also acts as a thrust plate to controlcamshaft endplay.

Fig. 6 Camshaft Position Sensor—SOHC

K

D

O

tri



NOCK SENSOR

ESCRIPTIONThe knock sensor threads into the cylinder block.

PERATIONWhen the knock sensor detects a knock in one of

he cylinders, it sends an input signal to the PCM. Inesponse, the PCM retards ignition timing for all cyl-nders by a scheduled amount.

Fig. 7 Target Magnet—Typical1 – CAM MAGNET/TARGET2 – CAMSHAFT POSITION SENSOR

Fig. 8 Target Magnet Polarity1 – TARGET MAGNET

Knock sensors contain a piezoelectric materialwhich constantly vibrates and sends an input voltage(signal) to the PCM while the engine operates. As theintensity of the crystal’s vibration increases, theknock sensor output voltage also increases.

NOTE: Over or under tightening affects knock sen-sor performance, possibly causing improper sparkcontrol.

IGNITION SWITCHIn the RUN position, the ignition switch connects

power from the Power Distribution Center (PDC) to afuse in the fuse block, back to a bus bar in the PDC.The bus bar feeds circuits for the Powertrain ControlModule (PCM), Proportional purge solenoid, EGRsolenoid, and ABS system. The bus bar in the PDCfeeds the coil side of the radiator fan relay, A/C com-pressor clutch relay, and the fuel pump relay. It alsofeeds the Airbag Control Module (ACM)

LOCK KEY CYLINDER

DESCRIPTIONThe lock cylinder is inserted in the end of the

housing opposite the ignition switch.

OPERATIONThe ignition key rotates the cylinder to 5 different

detents (Fig. 9) :• Accessory• Off (lock)• Unlock• On/Run• Start

Fig. 9 Ignition Lock Cylinder Detents

I

O

hictpvsI

R

S

rs

R

t1

w

I

i

t

Eu

S

rs

R

t1

I

Eu



GNITION INTERLOCK

PERATIONAll vehicles equipped with automatic transaxles

ave an interlock system. The system prevents shift-ng the vehicle out of Park unless the ignition lockylinder is in the Off, Run or Start position. In addi-ion, the operator cannot rotate the key to the lockosition unless the shifter is in the park position. Onehicles equipped with floor shift refer to the - Tran-axle for Automatic Transmission Shifter/Ignitionnterlock.

EMOVAL AND INSTALLATION

PARK PLUG SERVICEFailure to route the cables properly could cause the

adio to reproduce ignition noise, cross ignition of thepark plugs or short circuit the cables to ground.

EMOVALREMOVE CABLES FROM COIL FIRST.Always remove the spark plug cable by grasping

he top of the spark plug insulator, turning the boot/2 turn and pulling straight up in a steady motion.(1) Remove the spark plug using a quality socketith a rubber or foam insert.(2) Inspect the spark plug condition.

NSTALLATION(1) To avoid cross threading, start the spark plug

nto the cylinder head by hand.(2) Tighten spark plugs to 28 N·m (20 ft. lbs.)

orque.(3) Install spark plug insulators over spark plugs.nsure the top of the spark plug insulator covers thepper end of the spark plug tube.Reconnect to coil.

PARK PLUG CABLE SERVICEFailure to route the cables properly could cause the

adio to reproduce ignition noise, cross ignition of thepark plugs or short circuit the cables to ground.

EMOVALRemove spark plug cable from coil first.Always remove the spark plug cable by grasping

he top of the spark plug insulator, turning the boot/2 turn and pulling straight up in a steady motion.

NSTALLATIONInstall spark plug insulators over spark plugs.nsure the top of the spark plug insulator covers thepper end of the spark plug tube. The connect the

other end to coil pack. Be sure that dual plastic clipholds the cables off of the valve cover.

IGNITION COILThe electronic ignition coil pack attaches directly

to the valve cover (Fig. 11).

REMOVAL(1) Disconnect electrical connector from coil pack

(Fig. 10).

(2) Remove coil pack mounting bolts.(3) Remove coil pack.

INSTALLATION(1) Install coil pack on valve cover.(2) Transfer spark plug cables to new coil pack.

The coil pack towers are numbered with the cylinderidentification. Be sure the ignition cables snap ontothe towers.

AUTOMATIC SHUTDOWN RELAYThe relay is located in the Power Distribution Cen-

ter (PDC) (Fig. 12). The PDC is located next to thebattery in the engine compartment. For the locationof the relay within the PDC, refer to the PDC coverfor location. Check electrical terminals for corrosionand repair as necessary.

CAMSHAFT POSITION SENSORThe camshaft position sensor is mounted to the

rear of the cylinder head (Fig. 13).

Fig. 10 Electronic Ignition Coil Connector1 – COIL2 – LOCKING TAB

R

na

p

s

o


REMOVAL AND INSTALLATION (Continued)

EMOVAL(1) Remove brake booster hose and electrical con-

ector from holders on end of cylinder head covernd reposition.(2) Disconnect electrical connectors from camshaft

osition sensor.(3) Remove camshaft position sensor mounting

crews. Remove sensor.(4) Loosen screw attaching target magnet to rear

f camshaft (Fig. 14).

Fig. 11 Electronic Ignition Coil Pack1 – IGNITION COILS2 – SPARK PLUG CABLE3 – SPARK PLUG INSULATOR

Fig. 12 Power Distribution Center (PDC)

INSTALLATIONThe target magnet has two locating dowels that fit

into machined locating holes in end of the camshaft.(1) Install target magnet in end of camshaft.

Tighten mounting screw to 3.4 N·m (30 in. lbs.)torque.

(2) Install camshaft position sensor. Tighten sensormounting screws to 9 N·m (80 in. lbs.) torque.

(3) Place brake booster hose and electrical harnessin holders on end of valve cover.

(4) Attach electrical connectors to camshaft posi-tion sensor.

Fig. 13 Camshaft Position Sensor Location

Fig. 14 Target Magnet Removal/Installation1 – TARGET MAGNET2 – MOUNTING BOLT3 – REAR OF CYLINDER HEAD

C

ef

R

p

I

a

t

K

i

R

s

s

I

1ic



RANKSHAFT POSITION SENSORThe crankshaft position sensor mounts to the

ngine block behind the generator, just above the oililter (Fig. 15).

EMOVAL(1) Disconnect electrical connector from crankshaft

osition sensor.(2) Remove sensor mounting screw. Remove sensor.

NSTALLATION(1) Install sensor. Install sensor mounting screw

nd tighten.(2) Connect electrical connector to crankshaft posi-

ion sensor.

NOCK SENSORThe knock sensor threads into the side of the cyl-

nder block in front of the starter (Fig. 16).

EMOVAL(1) Disconnect electrical connector from knock sen-

or.(2) Use a crow foot socket to remove the knock

ensors.

NSTALLATION(1) Install knock sensor. Tighten knock sensor to

0 N·m (7 ft. lbs.) torque. Over or under tighten-ng effects knock sensor performance, possiblyausing improper spark control.(2) Attach electrical connector to knock sensor.

Fig. 15 Crankshaft Position Sensor1 – CRANKSHAFT POSITION SENSOR2 – GENERATOR3 – OIL FILTER

IGNITION SWITCHThe ignition switch attaches to the lock cylinder

housing on the end opposite the lock cylinder (Fig.17). For ignition switch terminal and circuit identifi-cation, refer to the Wiring Diagrams sections.

REMOVAL(1) Disconnect negative cable from battery.(2) Place key cylinder in RUN position. Through

the hole in the lower shroud, depress lock cylinderretaining tab and remove key cylinder (Fig. 18).

(3) Remove upper and lower shrouds from steeringcolumn.

Fig. 16 Knock Sensor

Fig. 17 Ignition Switch—Viewed From BelowColumn

1 – IGNITION SWITCH2 – LOCK CYLINDER HOUSING3 – RETAINING TABS

s

1

t

I

tt

sI



(4) Disconnect electrical connectors from ignitionwitch.(5) Remove ignition switch mounting screw (Fig.

9) with a #10 Torxt bit.

(6) Depress retaining tabs (Fig. 20) and pull igni-ion switch from steering column.

NSTALLATION(1) Ensure the ignition switch is in the RUN posi-

ion and the actuator shaft in the lock housing is inhe RUN position.

(2) Carefully install the ignition switch. Thewitch will snap over the retaining tabs (Fig. 21).nstall mounting screw (Fig. 19).

Fig. 18 Steering Column Shrouds1 – SCREW ACCESS HOLE2 – TAB ACCESS HOLE3 – LOWER SHROUD

Fig. 19 Ignition Switch Mounting Screw1 – MOUNTING SCREW2 – IGNITION SWITCH

(3) Install electrical connectors to ignition switch.(4) Install upper and lower shrouds.(5) Install key cylinder (cylinder retaining tab will

depress only in the RUN position).(6) Connect negative cable to battery.

(7) Check for proper operation of ignition switchand key-in warning switch.

LOCK KEY CYLINDERThe lock cylinder is inserted in the end of the

housing opposite the ignition switch. The ignition keyrotates the cylinder to 5 different detentes (Fig. 22) :

• Accessory• Off (lock)• Unlock

Fig. 20 Removing Ignition Switch1 – DEPRESS RETAINING TABS2 – IGNITION SWITCH

Fig. 21 Ignition Switch Installation1 – LOCK CYLINDER HOUSING2 – SHAFT

R

tr

I

pd

wti



• On/Run• Start

EMOVAL(1) Disconnect negative cable from battery.(2) Place key cylinder in RUN position. Through

he hole in the lower shroud, depress lock cylinderetaining tab and remove key cylinder.

NSTALLATION(1) Install key in lock cylinder. Turn key to run

osition (retaining tab on lock cylinder can beepressed).(2) The shaft at the end of the lock cylinder alignsith the socket in the end of the housing. To align

he socket with the lock cylinder, ensure the socket isn the Run position (Fig. 23).

Fig. 22 Ignition Lock Cylinder Detentes

Fig. 23 Socket in Lock Cylinder Housing1 – LOCK CYLINDER HOUSING2 – SOCKET

(3) Align the lock cylinder with the grooves in thehousing. Slide the lock cylinder into the housinguntil the tab sticks through the opening in the hous-ing.

(4) Turn the key to the Off position. Remove thekey.

(5) Connect negative cable to battery.

IGNITION INTERLOCKRefer to the Transaxle section for Shifter/Ignition

Interlock Service.

SPECIFICATIONS

VECI LABELAlways use the information found on the Vehicle

Emission Control Information (VECI) label. TheVECI label is located in the engine compartment.

FIRING ORDER—2.0L

T

S

I


SPECIFICATIONS (Continued)

ORQUE SPECIFICATION

DESCRIPTION TORQUECamshaft Position Sensor Screw . . . . . . . . . . 9 N·m

(80 in. lbs.)SOHC Cam Magnet/Target . . . 3.4 N·m (30 in. lbs.)Crankshaft Position Sensor Screw . . . . . . . . 9 N·m

(80 in. lbs.)Coolant Temp. Sensor . . . . . 18.6 N·m (165 in. lbs.)Ignition Coil to Cyl. Head . . 11.9 N·m (105 in. lbs.)Knock Sensor . . . . . . . . . . . . . . 10 N·m (90 in. lbs.)MAP/IAT Sensor Plastic Manifold . . . . . . . . . 2 N·m

(20 in. lbs.)
Spark Plugs . . . . . . . . . . . . . . . . 28 N·m (20 ft. lbs.)
SPARK PLUG CABLE RESISTANCE—SOHC

CABLE RESISTANCE

#1,#4 3500 ohms— 4900 ohms

#2,#3 2950 ohms— 4100 ohms

PARK PLUG

Engine Spark Plug Gap Thread Size

2.0L RC9YC 0.033 TO 0.038 14mm (3/4 in.) reach

GNITION COIL

Coil ManufacturePrimary Resistance at 21°C-27°C(70°F-80°F)

Secondary Resistance at 21°C-27°C(70°F-80°F)

Weastec (Steel Towers) 0.45 to 0.65 Ohms 11,500 to 13,500 Ohms

Diamond (copper towers) 0.53 to 0.65 Ohms 10,900 to 14,700 Ohms

Coil Polarity

Coil Polarity

ignition system - ertyu.org system table of contents ... voltage switches from low (metal) to high...

Documents