26
- FORM NO. 56043129 - SR 1900
Troubleshooting Guide
Symptom
GM 1.6L 4 cylinder engine will crank but not start
Part B:
Note 1: Check for 12V’s at the CB5 ignition circuit breaker 10A. If no input voltage @ the
Orn/Grn wire repair or replace wiring or key switch. Note 2: Check the fuel supply (empty
tank). Note 3: Check the condition of the spark plugs, replace if needed.
Follow the preliminary system checks listed below for engine cranks but does not start
Fuel System Checks LP
• Check for air intake system leakage between the mixer and throttle body.
• Verify proper operation of the low pressure lock-off solenoid valve.
• Check the fuel system pressure. Refer to the LPG fuel system diagnosis for instructions &
Specification.
• Check for proper mixer air valve operation. Note the air valve must vibrate back & forth when
cranking. No vibration look for an intake system leak. Example: The block-off injector plugs
loose or missing.
• Reference the 1.6L tier 2 engine service manual and follow the LPG system diagnosis.
Fuel System Checks for Gasoline
• Check fuel pump electrical circuit, fuel pump pressure and fuel rail pressure.
• Check electrical connections at the fuel injection solenoids.
• Check for air intake system leakage between the throttle body & intake manifold sealing
surfaces. Also any vacuum hoses for splits, kinks and proper connections
• Reference the 1.6L tier 2 engine service manual and follow the gasoline system diagnosis.
Sensor Checks
• Check the TMAP sensor.
• Check the magnetic pickup sensor (RPM).
Miscellaneous Electrical and Visual Checks
•Check engine harness wiring for proper connections, pinches or cuts.
•Check the ECM & engine ground for: tight clean connection, size and proper location.
•Check spark plug wires for: cracking/hardness, tight connections, proper routing & firing order.
•Check thoroughly for any type of a leak or restriction. Examples: Intake filter blocked, exhaust
restriction @ muffler (Cat), a leaking exhaust manifold etc.
Troubleshooting continued
from previous page
ENGINE SYSTEM
TROUBLESHOOTING GUIDE
Содержание 56507009
Страница 5: ...FORM NO 56043129 SR 1900 5...
Страница 64: ...64 FORM NO 56043129 SR 1900 THIS PAGE IS INTENTIONALLY BLANK...
Страница 76: ...76 FORM NO 56043129 SR 1900 ENGINE HARNESS FOR GM 1 6L GAS Petrol Tier 3 ELECTRICAL SYSTEM...
Страница 77: ...FORM NO 56043129 SR 1900 77 ELECTRICAL SYSTEM ENGINE HARNESS FOR GM 1 6L LPG Tier 3...