All trouble codes → Camshaft / crankshaft timing (VVT) codes
Camshaft / crankshaft timing (VVT) codes
Modern engines vary valve timing with oil-pressure-driven cam phasers, and the computer checks that the camshaft and crankshaft stay in step. Low or dirty oil, a stuck phaser or solenoid, a stretched timing chain, or a cam/crank sensor fault set these codes. Because phasers live on clean oil at the right pressure, oil level and condition is always the first check.
Diagnose before extended driving.
Common causes
- Low or dirty engine oil
- Cam phaser / VCT solenoid
- Stretched timing chain
- Cam/crank sensor
First checks
- Check oil level and condition first — phasers depend on clean oil at the right pressure
- Compare desired vs actual cam angle in manufacturer live data
System: Fuel & air metering. This is general guidance for the generic OBD-II codes in this group; always confirm against the service information for your specific vehicle.
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