Variable valve timing and engine timing
P0011 — "A" Camshaft Position - Timing Over-Advanced or System Performance (Bank 1)
The ECU commands the camshaft phaser (variable valve timing) to a target angle, but the camshaft on bank 1 sits more advanced than commanded or does not follow the command. Engine timing is off, so idle, power and emissions suffer.
Common causes
- Low, dirty or wrong-grade engine oil
- Faulty or sticking VVT solenoid (oil control valve)
- Clogged oil screen or oil passage to the phaser
- Worn or sticking camshaft phaser
- Stretched timing chain or incorrect timing
Symptoms
- Rough idle or stalling
- Reduced power and poor fuel economy
- Check engine light
- Rattling noise at start-up
How to check
- Check oil level and condition; change oil and filter if it is old or sludgy
- Inspect the VVT solenoid connector and wiring, then test the solenoid resistance
- Remove and clean the solenoid screen, check it moves freely
- Compare camshaft and crankshaft signals on a scan tool, and check timing chain stretch
Can you keep driving?
Short drives are usually possible, but fix it soon: poor oil flow or a worn chain can end in serious engine damage. Stop if the engine rattles loudly or stalls.
Related codes
Frequently asked questions
- What does P0011 mean?
- The camshaft on bank 1 is more advanced than the ECU commanded, or the variable valve timing system does not respond as expected.
- Can low oil cause P0011?
- Yes. VVT systems are driven by oil pressure, so low or dirty oil is one of the most common causes.
General reference information. It does not replace a diagnosis on your own vehicle. The same code can have different causes depending on make, model year and engine; check the manufacturer's documentation or ask a technician with a scan tool.