P0021 — "A" Camshaft Position - Timing Over-Advanced (Bank 2)
The bank 2 intake camshaft is more advanced than commanded, or the actuator does not respond as expected. Often caused by stuck-open oil control valves, sludge in VVT passages, or low oil pressure.
General code reference. Confirm the definition and diagnostic procedure for your vehicle's year, model and engine. A stored code alone does not identify a failed part.
Affected components
- Camshaft position actuator
- Oil control valve
Possible causes to check
These are possible checks, not a ranked diagnosis. Follow the vehicle manufacturer's test procedure before replacing parts.
- Oil control valve stuck (advance)
- Sludge in VVT passages
Possible symptoms
- Check engine light on
- Power loss especially in mid-rpm range
- Possible rough idle or stalling
- Increased fuel consumption
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
- A drive cycle may be required after repair
Related codes
Sources
Check each reference's vehicle and model-year scope. General background links do not establish which fault is most likely on your vehicle.
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.