P0012: A Camshaft Position Timing Over-Retarded (Bank 1)

Common causes

• Low oil level or the wrong oil viscosity
• A sticking or failing oil control valve (VVT solenoid)
• A worn cam phaser
• A stretched timing chain or a timing that's off by a tooth

Code meanings can vary slightly by manufacturer. Use these as a starting point and confirm with your vehicle's service information or a mechanic before replacing parts.

Symptoms

• Check engine light
• Rough idle
• Loss of power, especially at low speeds
• Rattling at startup on some engines

Is it safe to drive?

Check the oil level right away. If the engine rattles loudly or runs badly, limit driving until it's diagnosed.

How to check it with a scanner

1. Plug an OBD2 scanner into the port under the dashboard and read all stored codes and the freeze-frame data (the conditions when the code set).
2. Check the oil level and confirm it's the viscosity listed in your owner's manual.
3. Inspect the oil control valve screen (if it has one) for sludge.
4. Compare desired and actual cam angle in live data.
5. After a repair, clear the code and drive normally for a few days to confirm it doesn't come back.

A basic code reader shows the code; scanners with live data let you watch sensor readings, which is what you need for most of the checks above. See OBD2 scanners under $100.

Questions

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