this guide and the images herein are proprietary. … mechanic's guide...this guide and the...

This guide and the images herein are proprietary. Any unauthorized reproduction is prohibited.

GoWesty EFI Mechanic’s Guide

GoWesty Camper Products • 1119 Los Olivos Ave, Los Osos, CA 93402 • 888-469-3789 • www.gowesty.com

This guide is intended to help with diagnosing possible issues. The guide does not cover every possible issue or every possible cause. It is meant to be an aid—not a replacement—for standard combustion engine and modern fuel injection diagnostic procedures.

GoWesty EFI Main Component Overview

1. New Electronic Control Unit (ECU) • Replaces no-longer-available (NLA) Digifant ECU and Idle Control Unit (ICU) • Has standard OBD plug for diagnostics – Added feature • Compatible with standard real-time parameter displays, like ScanGauge –

Added feature • Capable of future software updates as needed– Added feature

2. Modern Throttle Position Sensor (TPS)

• Replaces antiquated and NLA factory throttle position switch • Obtains accurate throttle position • Located on the bottom of the throttle body

3. Modern Manifold Absolute Pressure (MAP) sensor – Added feature • Added sensor for better fuel management control • Used to get engine load and barometric pressure readings

4. New Oxygen Sensor • Replaces antiquated factory oxygen sensor • Modern 4-wire design with sealed electrical plug • Used to adjust fuel trims

5. New Knock Sensor and Controller – Added feature • Added sensor to protect engine against detonation/pre-ignition • Used to detect detonation/pre-ignition (knock) and retard timing to mitigate

detonation/ pre-ignition

6. Modern Distributor-less Ignition System-– Added feature • New electronic coil-on-plug ignition coils replaces antiquated factory single coil • GoWesty-designed cam position unit and crank position wheel replaces

antiquated distributor, cap, rotor, wires Used to determine crankshaft and camshaft position

7. Modern Mass Air Flow (MAF, aka “hotwire”) sensor in GoWesty-designed MAF housing

• Replaces antiquated and NLA factory air flow meter • Meters incoming air in order to control the amount of fuel used

8. GoWesty Tachometer Adapter

• Converts the digital tachometer signal from the more modern ECU to a signal that the factory tachometer will read

9. GoWesty-Designed All-New Engine Management Wiring Harness

• Replaces prone-to-moisture-intrusion, antiquated, corroded, and NLA factory harness

• All modern, completely sealed connectors for years of trouble-free service in all conditions




GoWesty EFI Component List

1. ECU 10. Chassis Ground 19. Cam Position Sensor Unit 2. Accessory Connector 11. Fuel Injector Connectors (X4) 20. Crankshaft Pulley Tone Wheel 3. Data Connector 12. Vehicle Connections and

Fuses 21. Crankshaft Position Sensor Unit

4. OBDII Adaptor 13. System Relays 22. Oxygen Sensor 5. Knock Controller 14. Tachometer Adapter 23. Fuel Pump Connectors 6. Body Grommet 15. A/C Connector 24. New Throttle Body 7. Wiring Harness 16. Coils (x4) 25. MAF Sensor and Housing 8. Coolant Temp Connector 17. Coil Brackets (x2) 26. Power Steering Connectors 9. Knock Sensor 18. MAP Sensor 27. Idle Air Control Valve

Connector




Clocking the Cam Position Unit The cam position unit must be clocked correctly in order for the engine to start.

The engine MUST be at top dead center (TDC) for cylinder #1 while lining up the cam

position unit.

1. After setting the engine to TDC for cylinder #1, loosen the adjuster clamp pinch bolt for the

cam position unit.

2. Remove the black plastic plug in the sight hole on top of the cam position sensor.

3. Rotate the cam position unit so that the trigger tooth is aligned in the center of the sight hole. Be sure to look through the sight hole straight-on in order to avoid alignment error.

4. Tighten the pinch bolt on the adjuster clamp.

5. Insert the black plastic plug back into the sight hole.

Trigger Sight Hole

Trigger Tooth




Cam Position Unit Exploded View

M6 BOLT

M6 WASHER

CAM POSITION SENSOR

SIGHT HOLE PLUG 4X M4 SCREWS

CAP PLATE

HOUSING TUBE

M6 BOLT M6 WASHER TRIGGER TOOTH

RETAINING RING FRICTION SHIM

4X COUNTERSUNK M6 SCREWS BASE PLATE

BRONZE BUSHING OIL SEAL

SHAFT HOUSING

4X M4 SCREWS

O-RING SEAL BRONZE BUSHING

DRIVE SHAFT

2X FRICTION SHIMS

DRIVE PIN DISTRIBUTOR DRIVE RING

DRIVE RING RETAINER




Crank Position System Overview

The GoWesty-designed crank position system is responsible for determining the position of the crankshaft at any given time. The crank position system is composed of two main components: a toothed wheel mounted on the inside of the crank pulley, and the crank sensor bracket assembly. Toothed Wheel

Assembly Diagram:

Crank Sensor Bracket Assembly:

This assembly mounts under the crankcase breather tower. This bracket locates the crank position sensor behind the toothed wheel shown in the figure above. The slots in the bracket mounting holes allow the spacing between the crank position sensor and the toothed wheel to be adjusted. The sensor should be about 0.75-1.5mm from the toothed wheel (about the thickness of a credit card). Rotate the pulley to ensure




the sensor does not contact the pulley or the toothed wheel.

Setting Timing

Prepare the engine to check and set timing advance:

A timing light will be needed to check and set the timing. You will need to temporarily place a factory-type spark plug wire between the #1 cylinder coil and the #1 cylinder spark plug to use a standard timing light. The coil will need to be disconnected from the bracket during this process. It will be necessary to push the spark plug wire fully into the coil and tape it in place using electrical tape during this process.

Cut boot from distributor end of factory style coil wire

Timing light inductor should be placed around spark plug wire per normal timing light usage.

Threaded tip may need to be removed during timing process

Insert conductor into Cylinder #1 Coil. Use electrical tape to hold in place while timing the engine.




NOTE: IT IS IMPERATIVE TO SET THE TIMING CORRECTLY. SETTING THE TIMING INCORRECTLY CAN CAUSE DAMAGE TO YOUR ENGINE AS WELL AS DRIVEABILITY AND IDLE ISSUES.

The timing is changed by loosening the lock bolt on the crank position sensor and turning the timing adjustment bolt. Turning the timing adjustment bolt will raise and lower the sensor which, in turn, will advance and retard the timing respectively. In other words, turning the bolt clockwise will raise the sensor and advance the timing. Turning the bolt counterclockwise will lower the sensor and retard the timing. Each full turn of the timing adjustment bolt is approximately equal to one degree of timing adjustment.

IMPORTANT!

Turn the engine off when tightening or loosening the lock bolt for the crank position sensor.

The V-belt pulley on all 1986-91 Vanagon water-boxer engines has a sharp, clearly visible notch on the part of the pulley closest to the engine block. This notch is the 5° before top dead center (BTDC) mark. There is another less-visible mark on the pulley on the next peak back (opposite side of that V-belt valley) further away from the block. That is the top dead center (TDC) mark. It is not a notch, but rather an indistinct depression that is about 10mm wide. These marks are both shown in the illustration below. When using a timing light, timing can be checked by observing the proximity of either of these marks in relation to the parting line of the engine block halves, which is straight up and down, directly in front of the pulley.

However, the hurdle when checking for 35 degrees at 3000 rpm is that there is no 35 degree mark on the pulley. To complicate matters, the only clearly visible mark on the pulley is a 5 degree BTDC mark. Thus, verifying 35 degrees at 3000 rpm takes some ingenuity. Here are methods that work well:

• Make a new 35 degree mark 1.75” clockwise from the 5 degree advanced mark. Once a 35 degree mark is present on the pulley, setting the timing to 35 degrees is a snap with any timing light and a tachometer. A template for making this mark is available in the Library section of the GoWesty Website located under Setting Timing on 1986-91 Vanagons.

• Using a timing light that has adjustable flash control and tachometer readout, simply dial in 30 degrees and use the 5 degree mark as a reference at 3000 rpm. The resulting setting will be 30 + 5, or 35 degrees at 3000 RPM!

Cra L

Timing Adjustment B

Once the timing is set correctly, shut off the engine and tighten the lock bolt on the sensor. Remove the spark plug wire and reinstall the coil on the spark plug.




Calibrating the Throttle Position Sensor (TPS) A scanner with live data can be used to check the TPS calibration while the engine is running. Scanners made for smart phones or a ScanGauge may be used, as well as many other high-quality scanners with live data capabilities. Find the Throttle Position Data in the scan tool. The TPS position should show 0% when the throttle body is completely closed. Open and close the throttle body several times to make sure that the scan tool shows a TPS reading of 0% each time the throttle body is shut. The TPS should show a reading of 0% just as the throttle plate is shut, and a reading larger than 0% just as the throttle plate is opened.

Upon installation of a new TPS, the TPS should be adjusted so that the resistance between pins 1 and 3 on the TPS read 1.05kΩ when the throttle is fully closed. The throttle body must be removed from the intake plenum and the TPS must be disconnected from the wiring harness to measure this resistance.

The system will learn and store the closed and wide-open throttle position during normal driving. If the TPS is relatively close to being calibrated properly, the learning function will correct the error.




Troubleshooting and Normal Sensor Values When troubleshooting an issue suspected to be related to the EFI system, start by scanning the ECU for codes with an OBDII-compliant scanner. The system should have the OBDII adapter (shown below) plugged in near the ECU. If not, the adapter will need to be located before plugging in the OBDII scanner.

A ScanGauge kit purchased from GoWesty is a great tool for diagnostics and monitoring, and includes extra non-standard OBDII live data values such as knock sensor voltage, knock retard, AC on/off, and power steering on/off. Not every issue will generate fault codes, but many problems can be easily diagnosed using a scanner with a live data readout function. A scanner with a live data readout will be more useful than a scanner which only reads diagnostic codes. The following tables show normal sensor values, abnormal readings, and possible causes to investigate. Coolant Temperature (ECT)

Normal Condition Abnormal conditions Possible Cause When fully warm: 95°C ±5°C (203°F±9°F)

Temperature runs below 90°C (194°F) when fully warm

Faulty coolant temperature sensor Faulty thermostat Incorrect thermostat

Temperature runs consistently above 100°C (212°F) when fully warm at idle

Faulty coolant temperature sensor Faulty thermostat: Temperature is truly too high Incorrect Thermostat: Temperature is truly too high Defective or damaged cooling system: Temperature is truly too high Faulty coolant temperature sensor Faulty thermostat: Temperature is truly too high

Temperature reads -40°C (-40°F) consistently

Temperature sender disconnected or open circuit




Air Intake Temperature (AIT) Normal Condition Abnormal Conditions Possible Cause

Engine completely cool: Air intake temperature ≈ Ambient Temperature

Temperature differs from ambient temperature by ±5°C with engine FULLY COOL

Faulty Mass Air Flow / Intake Air Temperature sensor

Temperature reads -40°C (-40°F) consistently

Temperature sender disconnected or open circuit

Throttle Position Sensor (TPS)

Normal Condition Abnormal Conditions Possible Cause Pedal fully released: Value should show between -3% to 0%

Value differs from these normal values

TPS is unplugged

TPS is improperly calibrated Pedal fully pressed: Value should

show between 95% to 110% TPS is defective

NOTE: Some scanners may not show >100% and may return to a value of 1 when 100% throttle is reached. This is normal and is not an issue. Load % (LOD)

Normal Condition Abnormal Conditions Possible Cause Load >93% at full throttle

Consistently above or below 44 to 60% at idle, fully warm

Incorrect ignition timing

Possible Worn Camshaft

Fueling Issue

Idle Air Control Valve Issue

Plugged Exhaust or Intake

Load % ≈50% at idle fully warm Load is above 60% at idle and fully warm

Intake leak Valve issue MAP Sensor vacuum line is disconnected, leaking or missing Idle Air Control Valve Malfunctioning

NOTE: Some scanners may not show >100% load and may return to a value of 1 when 100% load is reached. This is normal and is not an issue.




Manifold Absolute Pressure (MAP) Normal Condition Abnormal Conditions Possible Cause

MAP reading should show just under atmospheric pressure at full throttle

MAP shows >±10% deviation from atmospheric pressure at full throttle.

MAP sensor disconnected

MAP sensor faulty Mass Air Flow (MAF)

Normal Condition Abnormal Conditions Possible Cause MAF reading rises as engine RPM increases

MAF reading does not follow engine RPM

MAF sensor disconnected

MAF sensor faulty Idle Air Control Valve % Open (IAC) Shown as Commanded EGR % on most scanners

Normal Condition Abnormal Conditions Possible Cause 13-18% open at idle (fully warm at 900 to 1000 RPM)

IAC % is higher than 16% at idle (fully warm at 900 to 1000 RPM)

Idle air screw on throttle body is too far closed. Open idle air screw until normal conditions are met.

Engine idles fully warm at higher than 975 RPM, IAC shows 0%

Idle air screw on throttle body is too far open. Close idle air screw until normal conditions are met.

Oxygen Sensor Voltage (OXS)

Normal Condition Abnormal Conditions Possible Cause Fully warm below 75% load Voltage should continuously cycle up and down between about 0V to 1V.

Voltage stays solid near 0V for more than 30 seconds (under 75% Throttle)

Engine is running consistently lean. Look for any conditions that may make the vehicle run lean. Engine is consistently misfiring on one or more cylinders Oxygen sensor is faulty

Fully warm above 75% throttle Voltage should be greater than 0.7V

Voltage stays solid near .9V for more than 30 seconds (under 75% Throttle)

Engine is running consistently rich. Look for any conditions that may make the vehicle run rich. Oxygen sensor is faulty

NOTE: Fuel Trim Readings will NOT be accurate on an OBDII Scanner. Use the O2 sensor voltage above to diagnose any fueling issues.




Knock Voltage (KNV) *Non-standard. Custom programmed PID Normal Condition Abnormal Conditions Possible Cause

At idle Voltage should show ≈.2V to .5V at idle

Voltage is consistently below .2V at idle

Disconnected knock sensor Faulty knock sensor Faulty knock controller CPU

Voltage is consistently above .5V at idle

Engine noise is higher than usual. Check for loose components or abnormal noise. Faulty knock sensor

Voltage increases with engine RPM Voltage does not increase with RPM

Disconnected knock sensor Faulty knock sensor Faulty knock controller CPU

Voltage is consistently at ≈2.5V regardless of throttle position and engine RPM

Disconnected knock controller CPU

Knock Retard Degree (KNR) *Non-standard. Custom programmed PID

Normal Condition Abnormal Conditions Possible Cause Knock retard will show 0° under most driving conditions.

Low Octane Mode- The ECU will revert to a low octane timing map (constant timing retard) if the following conditions occur:

• Knock sensor or knock controller unit are disconnected or faulty.

• Knock events occur more than 10 times within 3 minutes

Incorrect timing setting- check timing

Fuel octane rating less than 91. If the ECU detects a knock condition, the ECU will retard the timing to prevent the engine from detonating. The ECU will hold this timing retard for 10 seconds before slowly returning the timing to normal advance conditions.

NOTE: Some false knock WILL be detected in some conditions where abnormal engine noises occur. Just because the ECU retards the timing, it DOES NOT NECESSARILY mean that the engine is experiencing knock. If the knock control system is retarding the timing very often, a trained technician should determine whether the system is retarding the timing due to true knock or due to an abnormal noise in the engine or surrounding area that could be falsely detected as knock by the system.




Air Conditioning (AC)*Non-standard. Custom programmed PID Normal Condition Abnormal Conditions Possible Cause

AC On Display should show “ON”

Display shows “OFF” when AC is turned on

AC signal wire disconnected AC clutch not engaging

AC Off Display should show “OFF” NOTE: When power is supplied to the AC clutch, the system will increase idle speed to account for the extra load of the AC compressor. If the engine is prone to stalling when the air conditioning is turned on, check the AC signal wire. Power Steering (PS) *Non-standard. Custom programmed PID

Normal Condition Abnormal Conditions Possible Cause Power Steering On Display should show “ON”

Display shows “OFF” when power steering is turned on

PS signal wire disconnected PS signal switch faulty

Power Steering Off Display should show “OFF”

this guide and the images herein are proprietary. … mechanic's guide...this guide and the...

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