Start and Stall

Symptom: Engine starts and runs normally, but stalls immediately or after a period of driving.

POSSIBLE CAUSE ACTION

PCM POWER AND GND CKT - Check connections for resistance or looseness. Verify B+ at PCM

SECONDARY IGNITION SYSTEM - Scope check Ignition System. Check SECONDARY CIRCUIT firing Kv and spark duration.

- Perform cylinder balance test.

- Remove spark plugs and inspect for: cracks, excessive wear, improper gap, burned electrodes, and wet or heavy deposits. Replace as necessary..

- Inspect distributor cap, rotor and spark plug wires for proper plug wire routing, crossfire between spark plugs (in cap) or wires, wires shorting to ground and rotor shorting to ground via distributor shaft.

- Check IGNITION TIMING for excessive spark advance or retard.

FUEL SYSTEM MALFUNCTION - Check fuel pressure.

- Check for lean Air-Fuel mixture, (O2S Sensor output).

- Perform injector balance test.

- Check fuel quality.

COOLANT SENSOR CALIBRATION - Verify Coolant sensor resistance values and compare with specs.


THROTTLE P0SITION SENSOR CALIBRATION - Perform voltage sweep test to check for drop outs.
- Scan check PCM for accurate coolant temp values.


MAP SENSOR CALIBRATION - Check vacuum at MAP sensor.
- Scan check PCM for proper MAP values at idle and WOT.
- Perform waveform analysis of MAP sensor output.

MINIMUM IDLE AIR FLOW - Perform minimum idle air test.

IDLE AIR CONTROL MOTOR OPERATION - Check AIS operation on Scan tool. Verify idle response for A/C on and off.