P0012 – Camshaft Position Timing Over Retarded (Bank 1)

Description

The P0012 code indicates that the Camshaft Position Timing for Bank 1 is more retarded (delayed) than the PCM expects. This typically occurs in vehicles equipped with Variable Valve Timing (VVT) systems. When the timing is “over-retarded,” it means the camshaft is staying in a retarded position longer than it should, leading to incorrect valve timing. This can result in poor engine performance, rough idling, and other drivability issues.

Bank 1 refers to the side of the engine that houses Cylinder 1.
This issue usually affects the intake camshaft timing.

Symptoms

- Rough idle
- Reduced engine performance or acceleration
- Engine stalling, especially at low RPMs
- Increased fuel consumption
- Engine misfires
- Difficulty starting the vehicle or failure to start
- Check engine light (CEL) illuminated
- Decreased power at higher RPMs
- Possible engine knocking or ticking noises

Common Causes

- Faulty camshaft position actuator (VVT solenoid)
- Low or dirty engine oil, which disrupts the VVT system’s performance
- Timing chain or belt that is stretched, worn, or misaligned
- Faulty camshaft position sensor
- Oil control valve (OCV) malfunction or blockage
- PCM malfunction (rare)
- Blocked or restricted oil passages affecting oil flow to the VVT system

Seriousness of the Issue

High: Driving with a delayed or over-retarded camshaft can lead to engine performance issues and, if left unresolved, could result in damage to the timing components, valves, and pistons. The vehicle may also enter limp mode to prevent further damage, reducing engine power significantly. Immediate attention is advised to prevent long-term engine damage.

How to Fix

Check the camshaft position actuator (VVT solenoid) for any malfunction. Clean or replace if necessary.
Change the engine oil and replace the oil filter if the oil is dirty or contaminated. Proper oil is crucial for the VVT system’s operation.
Inspect the timing chain or timing belt for signs of stretching, wear, or misalignment. Replace if necessary.
Test the camshaft position sensor to verify it’s reading correctly. Replace it if faulty.
Inspect the oil control valve (OCV) for blockages or malfunctions, and clean or replace as needed.
Check oil passages for blockages that could be preventing proper oil flow to the VVT system.
If no mechanical issues are found, inspect the PCM for malfunctions. Reprogram or replace it if necessary.