C0591 BMW Fault Code

Description:

Variable Cam Timing Over-advanced (Bank 1) The comprehensive component monitor (CCM) monitors the VCT position for an over-advanced camshaft timing.
The test fails when the camshaft timing exceeds a maximum calibrated value or remains in an advanced position.

BMW cam timing improperly set No oil flow to the VCT piston chamber Low oil pressure VCT solenoid valve stuck closed Camshaft advance mechanism binding (VCT unit) C0591 DTC is a check of the VCT unit.

C0591 Code Symptoms :

The scent may C0591 signal oil or coolant leaking from their normally closed-loop systems, or it may indicate dangerous exhaust gases invading your car's interior. Car and truck exhaust contains toxic gases such C0591, so if the inside of your car as if you were standing behind your car, get out and get it fixed.
Fight the urge to take a little nap first. So sleepy. That's the carbon monoxide talking, friends. At least open a window on your way to the shop.

Diagnosis And Repairing C0591

Parts or components should not be replaced with reference to only a C0591 DTC. The vehicle service manual should be consulted for more information on possible causes of the fault, along with required testing.

How to fix C0591 code ?

• Erratic camshaft position due to low oil pressure
• Continuous oil flow to the VCT piston chamber
• 1Camshaft Position Sensor circuit poor electrical connection
• Variable Camshaft Timing (VCT) position circuit is open or shorted

A good starting point in your diagnosis is checking all system fuses and fusible links. This can be done using the BMW DVOM on the voltage setting. You will want to test the fuses with circuits loaded.

Some fuses will appear normal until a load is placed on their respective circuit; at which point they will fail. This has been the cause of many 'phantom malfunctions'. Consult your vehicle information source for fuse and fusible link locations. If all fuses are in working order, you may want to check TCM relay operation by swapping identical relays. Usually the horn relay, starter relay, fuel pump relay, air conditioning clutch relay, and controller relays are similar enough in design to swap for diagnostic purposes.