Symptom Related Diagnostic Procedures

***UPDATED BY TSB 23123, JANUARY 1986

DIFFICULT COLD STARTING

1. Incorrect LH-control unit installed (see TSB update).

IDLE SPEED VARIES EXCESSIVELY

1. Incorrect CO adjustment.
2. Incorrect ignition timing.
3. Incorrect throttle valve adjustment.
4. Defective electronic control unit.
5. Defective air control valve.

IDLE SPEED TOO HIGH

1. Sticking air control valve.
2. Bad contact in connector.
3. Incorrect throttle switch adjustment.
4. Temperature sensor defective or disconnected.

NO IDLE SPEED CONTROL

1. Sticking air control valve.
2. Bad contact in connector.
3. Incorrect throttle switch adjustment.
4. Defective electronic control unit.
5. Defective air control valve.

ENGINE STALLS WHEN BRAKING TO STOP

1. Incorrect CO adjustment.
2. Incorrect ignition timing.
3. Incorrect throttle valve adjustment.
4. Bad contact in connector.
5. Defective electronic control unit.
6. System basic RPM setting too low.

NO FAST IDLE SPEED WHEN COLD

1. Sticking air control valve.
2. Defective electronic control unit.
3. Defective air control valve.
4. Defective coolant temperature sensor.