Circuit/System Testing

WARNING: This page is about a different variant/trim than selected.

Verify none of the following conditions listed below exist:
- Damage, carbon tracking or fluid intrusion of the spark plug boots and/or spark plugs
- Vacuum hose splits, kinks and incorrect connections
- Engine vacuum leaks
- Crankcase ventilation system for vacuum leaks
- Fuel pressure that is too low or too high. Refer to Fuel System Diagnosis .
- Contaminated fuel
- Exhaust system restrictions
  - If a condition exists
    Repair or replace as necessary.
  - If no conditions exist
Ignition OFF, remove the K35 Ignition Coil Module from the spark plugs and connect the EL 26792 HEI Spark Tester to the appropriate spark plug boot, engine Cranking.
NOTE: An erratic or weak spark is considered a no spark condition.
Verify the spark output.
- If no output or the output is weak
  Refer to Electronic Ignition System Diagnosis .
- If the output is good
Ignition OFF.
Verify the conditions listed below. Refer to Ignition System Specifications .
- The correct spark plug type
- The correct spark plug gap
- The correct spark plug torque
- If a condition exists
  Repair or replace as necessary.
- If no conditions exist
Exchange the suspect spark plug with another cylinder that is operating correctly.
Engine Running.
Verify the scan tool Cylinder 1-4 Current Misfire Counter does not increment for the cylinder where the suspect spark plug was installed.
- If increments
  Replace the spark plug.
- If does not increment
Test or inspect for the conditions listed below:
- A lean or rich Q17 Fuel Injector-Refer to Fuel Injector Diagnosis .
- An engine mechanical condition-Refer to Symptoms - Engine Mechanical .