Electronic Ignition (EI) System Diagnosis

CIRCUIT DESCRIPTION
This engine is equipped with a distributorless ignition system called the Electronic Ignition (EI) system. The primary circuit of the EI system consists of 2 separate ignition coils, an electronic Ignition Control (IC) module and a Crankshaft Position (CKP) sensor as well as the related connecting wires and the ignition control (IC) portion of the Powertrain Control Module (PCM). Each secondary circuit consists of the secondary winding of the coil, spark plug wires and the spark plugs.

IMPORTANT: The Camshaft Position (CMP) sensor is only used for a misfire detection and is not part of the ignition system.

DIAGNOSTIC AIDS
^ A small amount of resistance in the battery positive voltage circuit to the PCM may cause a no start. Test the battery positive voltage circuit for excessive resistance or corrosion. Refer to Wiring Repairs in Diagrams.
^ The PCM grounds will cause a NO START only if ALL of them are not making a good connection. Refer to Wiring Repairs in Diagrams.
^ If the CKP sensor is loose it may cause an intermittent NO START by moving away from the reluctor wheel. Inspect the sensor and matting surface for being clean and tight.

Diagnostic Chart (Part 1 Of 3):

Diagnostic Chart (Part 2 Of 3):

Diagnostic Chart (Part 3 Of 3):

TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table.
5. Repair the cause of the malfunctioning spark plugs before replacing.
6. Inspect for basic engine malfunction like low compression, burnt valves, a worn timing chain and worn gears, etc.
18. Any time the CKP sensor is removed the Crankshaft Position System Variation Learn Procedure must be performed.
21. The replacement PCM must be reprogrammed and the Crankshaft Position System Variation Learn procedure must be performed.