Symptom Related Diagnostic Procedures

Engine Does Not Start Or Difficult To Start When Cold Or Warm

1. Fuse No. 1 or 11 defective.
2. Defective ignition system.
3. Poor wire connection.
4. Air leakage in intake system.
5. Defective fuel pump.
6. Incorrect line pressure.
7. Defective air overpressure switch defective.

Poor Cold Starting

1. Defective coolant temperature sensor.

Surge During Engine Braking

1. Defective bypass valve.
2. Throttle switch incorrectly adjusted.

High Fuel Consumption

1. Disconnected coolant temperature sensor.
2. Fuel leakage.
3. Incorrect line pressure.
4. Incorrect CO level.

Rough Running During All Engine Speeds

1. Air leakage in intake system.
2. Defective injectors.
3. Incorrect line pressure.
4. Defective air mass meter.

Rough Idle

1. Air leakage in intake system.
2. Clogged or loose air control valve hoses.
3. Defective air control valve.
4. Incorrectly connected coolant temperature sensor.
5. Loose or incorrectly adjusted throttle valve.
6. Incorrectly adjusted throttle switch.
7. Ignition timing.
8. Incorrect line pressure or CO level.

Low Top Speed, Poor Performance

1. Incorrectly adjusted throttle linkage.
2. Ignition timing.
3. Air leakage in intake system.
4. Defective fuel pump.
5. Incorrect line pressure.
6. Defective bypass valve.
7. Incorrect charge pressure.