A Camshaft Position Timing Over-Advanced Bank 1
The Engine Control Module (ECM) detected that the Bank 1 intake camshaft timing is more advanced than the computer commanded. This typically occurs when the variable valve timing (VVT) system fails to retard the camshaft timing back to its base or requested position.
While the vehicle can usually still be driven, prolonged driving with incorrect camshaft timing can lead to poor performance, reduced fuel economy, and potential internal engine wear. It should be diagnosed and repaired soon to prevent further issues.
Common symptoms
- Illuminated Check Engine Light
- Rough idle or engine stalling
- Reduced engine power and poor acceleration
- Decreased fuel economy
- Engine rattling noise from the timing cover area
Likely causes
- Low engine oil level or dirty, degraded engine oil
- Faulty variable valve timing (VVT) control solenoid / oil control valve (OCV)
- Clogged VVT solenoid screen or restricted oil passages
- Worn or damaged timing chain, tensioner, or guides
- Faulty camshaft position sensor or wiring issues
- Damaged or failing VVT phaser/actuator
What to check before replacing parts
Check the engine oil level and condition.
Look for: Oil that is significantly low, excessively dirty, or sludged, which prevents proper hydraulic operation of the VVT system.
Scan for related DTCs and monitor live data.
Look for: Commanded versus actual camshaft position angles on a scan tool; a significant variance indicates the phaser is not moving as requested by the ECM.
Inspect and test the VVT solenoid (Oil Control Valve).
Look for: Electrical resistance out of specification (usually 6-12 ohms) or a mechanical valve that sticks when manually energized with a 12-volt source.
Remove and inspect the VVT solenoid screens and mounting area.
Look for: Metal shavings, sludge, or debris clogging the screens, which restricts oil flow to the camshaft phaser.
Inspect the timing chain and phaser assembly if external checks pass.
Look for: A stretched timing chain, broken guides, or a mechanically locked/damaged VVT phaser requiring mechanical replacement.
This page explains the generic P0011 definition and is general reference information, not a diagnosis for your specific vehicle. Actual causes, severity, and repairs vary by make, model, engine, and mileage — always confirm with a scan tool and a qualified technician before replacing parts.
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