Error code P0012 is a generic code which indicates that ECM believes the intake camshaft timing for bank 1 is more retarded that it was instructed to be. This condition can be detected during the advancing or retarding section of the camshaft timing process.

Common Symptoms

  • The if ECM is unable to command the timing to move, the Check Engine Light will be illuminated
  • The retarded starting position may cause the engine to have a hard start
  • The issue with camshaft positioning may lead to higher fuel consumption
  • The engine may become prone to stalling or running rough depending on the camshaft position
  • The increased fuel consumption means the car is likely to fail an emissions test

Possible Causes

  • The camshaft phaser may be damaged and stuck in the retarded position
  • The VCT oil control valve could be stuck in the open position
  • There may be oil flow problems to the phaser and the VCT piston

What To Check

  • Inspect all the connections to the sensor in the camshaft and the oil control solenoid valve, looking for damaged wiring or loose connections
  • Check the engine oil to ensure it’s clean and the viscosity matches the manufacturer’s recommendation
  • Take a screenshot of the error before resetting the code
  • Restart the vehicle and retest to see if the error returns
  • Turn the oil control solenoid off and on and monitor the camshaft timing to see if it changes
  • If nothing is found and the code is still being triggered, a pinpoint test may be required

How To Fix It

  • Reset all codes and perform a road test to see if it reoccurs
  • Change the oil filter and ensure the viscosity of the oil matches the manufacturers recommendations
  • Replace or repair the wiring and connections to the camshaft oil control solenoid
  • Replace the camshaft oil control valve for the bank 1 intake camshaft
  • Check the timing chain alignment for any potential issues

Additional Tips

When attempting to repair the P0012 error code it’s important to verify the exact cause of the error. Visual inspections should be performed to correct any obvious issues, while a pinpoint diagnosis will ensure that the correct fault is repaired.

The timing of the advance and retard is controlled by camshaft phaser controls using oil and oil pressure. Due to the nature of these components, the oil needs to be the right viscosity in order for it to function as intended. If the oil is too thick the system can malfunction and trigger a number of error codes. It can also cause various issues with the engine. The use of the wrong kind of oil can trigger code P0012, as well as various other related error codes.