Initial Inspection and Diagnostic Overview

INSUFFICIENT ENGINE OUTPUT
Low Supercharged Pressure
1. Defective wastegate valve.
2. Defective relief valve.
3. Compressed air leakage.
4. Exhaust gas leakage.
5. Defective turbocharger.

RELIEF VALVE IN OPERATION
1. Defective wastegate valve.

``CHECK ENGINE'' LAMP, ON
1. Defective wastegate valve and relief valve.

FREQUENT ENGINE KNOCK
Excessive Supercharged Pressure
1. Wastegate valve, relief valve and ECM fuel cut operation all simultaneously defective.

TOO WHITE EXHAUST GAS
1. Defective turbocharger oil seal.