DIY Fix ! ! We had a random check engine light on a 2009 Ford Escape that would go away and pop back up over a 2-6 month spread.
- P0012: A Camshaft Position - Timing Over-Retarded (Bank 1)
- P0022: A Camshaft Position - Timing Over-Retarded (Bank 2)
There are two overhead camshafts on this V6 motor. One for each set of three cylinders. Troubleshooting the codes is the same. I only posted about P0012 below to shorten the article.
Quote:
P0012 code definition
Camshaft Position “A” - Timing Over-Retarded (Bank 1)
What the P0012 code means
P0012 is the OBD-II generic code indicating the engine control module (ECM) has determined that the intake camshaft timing for bank 1 is more retarded than what the ECM has commanded it be. This over-retarded timing condition could be during the advancing or retarding phase of the camshaft timing.
What causes the P0012 code?- The variable camshaft timing (VCT) oil control valve (OCV) stuck in the open position.
- The camshaft phaser is damaged and stuck in the retarded position.
- Oil flow problems to the VCT piston and phaser.
What are the symptoms of the P0012 code?- The ECM will turn on the Check Engine Light if the timing cannot be commanded to move.
- The engine will have a hard start condition due to the retarded timing position.
- Fuel mileage may go down since the camshaft is not in a position to get the best possible fuel mileage.
- Depending on camshaft position the engine may stall, hesitate, and run rougher than normal.
- The vehicle will fail an emissions test.
Note: Your drive problems will change depending on the camshaft timing positions when the camshaft stopped advancing.
How does a mechanic diagnose the P0012 code?- Visually checks the electrical connections to the camshaft sensor, oil control solenoid valve, and crankshaft sensor for loose connections, damaged wiring harness, or any other issues that may cause a problem.
- Makes sure the engine oil is full of clean correct viscosity oil.
- The technician will scan and document the codes received and view the freeze frame data to see when the code was set.
- The codes should then be reset to clear the OBD-II fault codes and retest the vehicle to see if the P0012 code comes back.
- Commands the oil control solenoid valve on and off to see if the camshaft timing changes.
- If no problems are noted and the code still exists, then the next step for the technician is to perform a manufacturer's specific pinpoint tests for the P0012 code and repair as needed.
Note: Follow the manufacturer's recommended pinpoint test to narrow down the problem, since each engine may be tested differently and possible engine internal damage may be done if tests are not performed in accordance with a correct procedure.
Common mistakes when diagnosing the P0012 code?
Follow these simple guidelines to prevent mistakes:- Always verify the failure before attempting any repairs.
- Do a thorough visual check for any problems with the wiring or connections to the components.
- Follow the pinpoint test step-by-step to help prevent a misdiagnosis.
- Do not replace any parts unless directed by the pinpoint or visual testing.
How serious is the P0012 code?- The engine may run erratic and stall, hesitate, run rough or have a hard starting condition.
- The engine may have excessive fuel consumption, carbon fouling of engine components, and various drive complaints depending on the camshaft failed position.
- Driving the vehicle for a prolonged time with the camshafts not retarding may cause other problems to the valve train or engine depending on the cause of the failure.
What repairs can fix the P0012 code?- Resetting the fault codes and performing a road test.
- Changing the oil and filter to the proper oil viscosity for the engine's specifications.
- Repairing or replacing the wiring or connection to the camshaft oil control solenoid.
- Replacing the camshaft oil control valve for bank 1 intake camshaft.
- Check the timing chain alignment for jumped timing problems and repair as needed.
Additional comments for consideration regarding the P0012 code
The camshaft phaser controls the timing advance and retard function through oil pressure and oil. The oil needs to be the proper viscosity for the camshaft timing control to work as designed. If you use too thick of oil it can cause this system to malfunction and cause codes and running issues with the engine. Incorrect oil can cause this code and may cause multiple codes along with it.
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Let's take it apart !
We have checked everything checkable, flushed the system, and now are down to part replacement.
- Remove front end, intake manifold, valve covers, and replace Variable Camshaft Timing (VCT) solenoid.
- Reassemble with no parts left over.
The Variable Camshaft Timing (VCT) solenoids pop up out of the valve cover through a rubber O-ring on our vehicle.
- There was tons of sludge to clean up.
- The rubber O-rings got hard over time and leaked (120K+ miles). This allowed dirt to fall into the valve covers over time and mix w/ the oil and turned into a sludge. An oil flush was good , but could not get the gunk off and the solenoids that were caked up.
Variable Camshaft Timing (VCT) solenoids
Out with the old parts and in with the new parts.
We also bought a new gasket set kit and replaced everything.
Once we put it all back together and replaced the oil and oil filter everything was good !
All done and no extra parts !!!!!