P0012 "A" Camshaft Position - Timing Over-Retarded (Bank 1)
P0012 is a generic OBD2 powertrain code. It means “"A" Camshaft Position - Timing Over-Retarded (Bank 1)” — the same on every make and model, because the definition comes from the SAE J2012 standard rather than from the carmaker.
Ask the AI about P0012 on your car- System
- Powertrain (P)
- Code type
- Generic (SAE)
- Range
- P00xx
- Urgency
- Moderate
What P0012 means
Variable valve timing turns the camshaft relative to the crankshaft using engine oil pressure. The computer commanded a position for the intake camshaft on bank 1 and measured it further advanced or retarded than it should be.
Symptoms
- A rough idle or stalling
- Loss of power, especially at low revs
- A rattle for a second or two on a cold start
- Worse fuel economy
Most likely causes
- Low, old or wrong-grade engine oil — the cam phaser works on oil pressure
- A sticking oil-control (VVT) solenoid or its clogged filter screen
- A worn camshaft phaser
- A stretched timing chain or worn guides
What to check first
- Check the oil level and when it was last changed — often the whole fix is an oil change with the correct grade
- Test and clean the oil-control solenoid
- If a crankshaft–camshaft correlation code (P0016–P0019) or a cold-start rattle comes with it, have the timing chain checked
Can I keep driving with P0012?
Drivable — plan the repair soon
Yes, carefully, to the workshop — after checking the oil level. If the engine rattles or a correlation code (P0016–P0019) appears as well, stop driving: the chain may be about to jump.
What the wording tells you
Bank 1: engines with two rows of cylinders — V6, V8, boxer — have two banks. Bank 1 is the side that holds cylinder 1, bank 2 the other side; an inline engine has only bank 1.
Camshaft “A”: by the SAE convention “A” is the intake (or left/front) camshaft and “B” the exhaust (or right/rear) one — here, the intake camshaft.
How P0012 breaks down
Powertrain. Engine, transmission, fuel and emissions — the codes behind the check engine lamp.
Generic code: defined by SAE, the same on every make.
Fuel & air metering and emission controls.
The specific fault within this range.
Where to look: Fuel & air metering and emission controls
Codes in these ranges cover the parts that decide how much air and fuel reach the engine and how the exhaust is treated on the way out: variable valve timing, oxygen-sensor heaters, turbo boost control, the electronic throttle and accelerator pedal, intake runners, NOx sensors and — on diesels — the particulate filter and the AdBlue (SCR) system.
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Frequently asked
What does P0012 mean?
P0012 is a generic OBD2 powertrain code. It means “"A" Camshaft Position - Timing Over-Retarded (Bank 1)” — the same on every make and model, because the definition comes from the SAE J2012 standard rather than from the carmaker. Variable valve timing turns the camshaft relative to the crankshaft using engine oil pressure. The computer commanded a position for the intake camshaft on bank 1 and measured it further advanced or retarded than it should be.
Can I drive with P0012?
Yes, carefully, to the workshop — after checking the oil level. If the engine rattles or a correlation code (P0016–P0019) appears as well, stop driving: the chain may be about to jump.
What causes P0012?
Low, old or wrong-grade engine oil — the cam phaser works on oil pressure; A sticking oil-control (VVT) solenoid or its clogged filter screen; A worn camshaft phaser; A stretched timing chain or worn guides.
How do I clear P0012?
Fix the cause first, then clear it with any OBD2 scanner or app. Once the fault is gone the car also clears it on its own: the check engine lamp goes off after the self-test passes on three drive cycles in a row, and the stored code ages out after about 40 warm-ups. Clearing without a repair only hides it for a while — and resets the readiness monitors an emissions inspection looks at.
Is P0012 the same on every car?
Yes. P0012 is a generic SAE J2012 code, so its definition is identical on every make and model. What differs is the cause behind it and the repair procedure, which depend on the engine — that’s why the assistant on this page asks for your car.
Guides
Definitions: the generic SAE J2012 codes from Brimly’s offline dictionary (data version 2026.09). Causes and advice are general guidance for all makes — the service information for your car has the last word.