P0011: "A" Camshaft Position - Timing Over-Advanced or System Performance (Bank 1)
Title: SAE J2012 generic definition. Manufacturer-specific definitions and enhanced codes can differ; check service information for the exact vehicle.
What P0011 means
On bank 1, the intake ("A") camshaft isn't where the ECM commanded it: it's too advanced or responding poorly.
What sets it
Engines with variable valve timing use oil pressure, routed through an oil control valve (OCV), to rotate a cam phaser. The ECM compares the commanded cam angle with the actual angle from the cam sensor. If the error is too large for too long, it sets P0011. Oil condition and supply matter as much as the electrical parts.
Symptoms
- Rough idle, especially hot
- Stalling or hesitation
- Reduced power or economy
- Rattle on start-up on some engines
Is it safe to drive?
General guidance, not a guarantee: Often drivable short-term, but low oil level or pressure can cause severe engine damage. Check the oil level before driving further. If in doubt, have it towed and diagnosed.
Common causes
Listed roughly from most to least common in general practice. The real order varies by vehicle, mileage and history.
- Low oil level, sludge or wrong viscosity: phasers need clean oil at the right viscosity
- Sticking OCV or clogged OCV screen
- Phaser sticking or worn
- Timing chain stretch or guide wear
- OCV circuit fault (often sets other codes too)
Test before you replace: diagnostic sequence
General guidance only. Always follow the vehicle manufacturer's service information, specifications and safety procedures. Any figures below are general guidelines that defer to the manufacturer's specification.
- Check oil level, condition and grade against the manufacturer specification. Ask when the oil was last changed.
- In live data, compare desired versus actual intake cam angle at idle and during a gentle rev.
- Command the OCV with the scan tool (where supported) and watch the actual cam angle respond.
- Inspect the OCV and any oil screen for debris, following the manufacturer's access procedure.
- If cam/crank correlation looks off at rest, inspect timing components (see P0016).
- After repair, verify desired and actual angles track each other.
Bench note: Ask the customer about oil changes before you condemn the phaser. Old or wrong-grade oil causes many VVT codes.
Related codes
FAQ
Can an oil change fix P0011?
Sometimes, if the oil was low, sludgy or the wrong viscosity. Verify with live cam-angle data afterward.
Is it the cam sensor?
Usually not. A sensor fault more often sets a circuit code. P0011 is about cam position not matching the command.
What does "A" camshaft mean?
In SAE terms, "A" is usually the intake camshaft, but confirm with the manufacturer's service information.
Sources
- SAE J2012, Diagnostic Trouble Code Definitions (standard page; code titles only)
- Generic code title cross-check: obd-codes.com generic code list
Written with AI assistance and reviewed for accuracy; not a substitute for OEM service information. Shop Docs Studio is not affiliated with SAE, EPA, CARB or any vehicle manufacturer.