- Intermittent Malfunctions

Problem may or may not turn "ON" the "MALFUNCTION INDICATOR" light, or store a code. The fault must be present to locate the problem. If the problem is intermittent, the use of the Trouble Codes charts may result in the replacement of good parts.



POSSIBLE CAUSE ACTION


Poor mating of the component Inspect connectors and
connector halves, or terminals re-attach if necessary.
not fully seated





Improperly formed or damaged terminals All connector terminals, within the problem circuit, should be carefully reformed to increase contact tension




If wiring and connectors are okay, Clear codes and test drive
and NO trouble codes are stored. vehicle. Try to isolate failure.
.




"MALFUNCTION INDICATOR" light 1. Ignition coil shorted to ground,
with NO codes stored arcing at spark plug wires or plugs
2. "MALFUNCTION INDICATOR" light, wire to ECM, shorted to ground
3. Diagnostic test terminal, wire to ECM, shorted to ground
4. ECM power grounds.
5. EMR circuit activated



Improper installation of electrical Check the wiring of the
options. (e.g. Lights, 2-way radios, Phone) accessory.
Re-route wires if necessary.




Electronic Spark Timing (EST) Re-route wires if
wires close to secondary wires, coil, necessary.
or generator