Spark Plug Connector Checking
- Remove screws from ignition coil mounting bracket (arrows). See Fig 1. Remove spark plugs. Disconnect harness connectors from all 5 fuel injectors.
- Install spark plugs in the spark plug connectors (if necessary, use new spark plugs) and place on the cylinder head cover as shown in the illustration. See Fig 2. Operate starter and check for spark at spark plugs.WARNING: During the test, DO NOT touch ignition coil mounting bracket or spark plugs. There is a danger of electrical shock.
- If there is weak or missing spark on one or more of the spark plugs: Repeat test using other spark plugs.
- If spark is still unsatisfactory: Remove spark plug connector involved. Measure resistance of the spark plug connector using DVOM, resistance must be approximately 5000 ohms. If resistance is not correct, replace spark plug connector. If resistance is okay, check voltage supply of ignition coils. See CHECKING VOLTAGE SUPPLY FOR IGNITION COILS . If the voltage supply is okay, check control of power output stages. See CHECKING CONTROL OF N122 & N127 POWER OUTPUT STAGES . If the control of the power output stages is Okay and the malfunction only occurs on one or another spark plug: Temporarily transpose the two power output stages as a test and repeat spark test.
- If the malfunction now occurs on other spark plugs: Replace defective power output stage. If the malfunction occurs again on the same spark plug: Replace respective ignition coil.