Diagnostic Aids

NOTE: If camshaft sensor signal is missing, ECM will not provide spark to both mating cylinders as well as default to non-sequential fuel injection. Engine will still start under this condition.

Use scan tool to perform IGNITION COIL test for each individual cylinder while listening closely for spark at appropriate ignition coil. Spark on one cylinder of the No. 1, 3, 5 bank and spark on another cylinder of the No. 2, 4, 6 bank indicates that each EI module power and ground circuits are okay.