Possible Causes
| Possible Causes |
|---|
| ENGINE VACUUM LEAK |
| EXCESSIVE CARBON BUILD-UP IN CYLINDER HEAD OR COMBUSTION CHAMBER |
| FAULTY FUEL INJECTOR |
| POOR FUEL QUALITY OR HIGH ETHANOL LEVEL |
| CRANKSHAFT POSITION SENSOR (CKP) OR TONE WHEEL ISSUES |
| FAULTY IGNITION COIL OR SPARK PLUG |
| VARIABLE VALVE LIFT (VVL) SYSTEM ISSUES (IF EQUIPPED) |
| COOLANT LEAKING INTO A CYLINDER |
| FAULTY CYLINDER HEAD GASKET |
| ENGINE MECHANICAL/LOW COMPRESSION |
| WORN CAMSHAFT LOBES, SPRINGS OR ROCKER ARMS |
| POWERTRAIN CONTROL MODULE (PCM) |
Always perform the PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .