P0012 means the intake camshaft on bank 1 is running later (more retarded) than the engine computer commanded, a fault in the variable valve timing (VVT) system. It is the opposite direction from P0011 (too far advanced) and a different fault from P0016, where cam and crank signals disagree. Because VVT is driven by oil pressure, the most common causes are low, dirty or wrong-grade oil and a sticking control solenoid.
What Does P0012 Mean?
Variable valve timing lets the computer shift the camshaft’s position relative to the crankshaft to suit the driving conditions — advancing it for power and retarding it for smooth idle and low emissions. A control solenoid directs pressurised engine oil to a phaser on the camshaft, which physically turns it. The computer compares where it asked the camshaft to be with what the camshaft sensor reports. P0012 is stored when the camshaft is consistently later than commanded.
Since oil does the moving, the first suspects are always oil level, oil condition and oil grade. See our how to check engine oil level properly guide. If the cam sensor and crank sensor signals disagree, you are more likely looking at P0016, P0341 or a timing chain problem than a pure VVT fault.
P0011 says the camshaft is further advanced than commanded; P0012 says it is further retarded. The causes overlap heavily, which is why an oil check is the first step for both.
Common Symptoms
- Check engine light on, sometimes with no change in how the car drives — see check engine light on but car runs fine.
- Rough idle or stalling — see car dies at idle.
- Reduced power and poorer fuel economy.
- A rattle or tick from the front of the engine, especially at start-up — see engine ticking noise.
- Limp mode in some cars — see car stuck in limp mode.
Common Causes, Most Likely First
- Low engine oil level — see oil pressure light on.
- Dirty, sludged or overdue oil, which clogs the narrow passages and screens in the VVT system. See how often to change engine oil.
- The wrong oil grade — too thick to flow quickly — see synthetic vs conventional oil.
- A sticking or failed VVT control solenoid or a blocked solenoid screen.
- A worn VVT phaser (cam gear) that no longer holds position.
- A stretched timing chain or worn tensioner — see when to replace the timing belt for how seriously timing faults should be taken.
- A cam sensor or wiring fault — see P0340.
How to Diagnose It
- Check the oil level and condition with the engine off and level. Top up or change it if low or dirty.
- Confirm the oil grade matches the specification in your owner’s manual.
- Scan for other codes — cam sensor, crank sensor or correlation codes change the picture. See the OBD-II scanner guide.
- Clear the code after an oil change and see whether it returns.
- Inspect the solenoid and its screen and test its operation if the code returns.
- Have the timing checked if there is a rattle or the code comes back with a cam code.
Never work under a vehicle supported only by a jack. Use axle stands on firm, level ground, chock the wheels that stay down, and leave the car in gear or Park with the handbrake on. A jack lifts; stands hold.
Possible Fixes
| Cause | Fix | Typical cost |
|---|---|---|
| Low or dirty oil | Top up or change oil and filter with the correct grade | $10 – $120 |
| Sticking VVT solenoid | Clean or replace the solenoid | $100 – $350 |
| Worn VVT phaser | Replace the phaser | $400 – $1,200 |
| Wiring or sensor fault | Repair or replace | $80 – $350 |
| Stretched timing chain or tensioner | Replace chain, tensioner and guides | $1,200 – $3,500 |
Can I Drive With P0012?
Short trips only. Change the oil first if it is low or overdue — that fixes many cases. Do not keep driving with a rattle or a flashing check engine light: a timing fault left alone can damage the engine, and low oil can destroy it (see oil pressure light on and flashing check engine light).
When to See a Mechanic
If the code returns after an oil change with the correct grade, or you hear a rattle. Mention the oil change history. More in our engine section.
Frequently Asked Questions
What does P0012 mean?
The intake camshaft on bank 1 is later (more retarded) than the engine computer commanded, a fault in the variable valve timing system.
What is the difference between P0011 and P0012?
P0011 means the camshaft is further advanced than commanded; P0012 means it is further retarded.
Can low or dirty oil cause P0012?
Yes, and it is the most common cause, because variable valve timing is moved by engine oil pressure.
Should I change the oil first?
If it is low, dirty or overdue, yes — check the level and use the grade the manufacturer specifies, then see whether the code returns.
How much does it cost to fix P0012?
An oil change fixes many cases for $10–$120; a solenoid is $100–$350 and timing work can reach $1,200–$3,500.
