Skip the auto shop - Our mechanics make house calls

P0021 OBD-II Trouble Code: Camshaft Position A - Timing Over-Advanced or System Performance (Bank 2)

Check Engine Light

P0021 code definition

Camshaft Position A - Timing Over-Advanced or System Performance (Bank 2)

What the P0021 code means

P0021 is the OBD-II generic code indicating that the Engine Control Module (ECM) has determined that the bank 2 intake camshaft is more advanced than what the ECM has commanded it to be. This over advanced condition could be during advancing, or retarding of the camshaft timing.

What causes the P0021 code?

  • The camshaft is more advanced than the ECM has commanded it to advance.

  • The camshaft is more advanced when it has been commanded to retard to a lower timing level.

  • The Oil Control Valve (OCV) connected to the bank 2 camshaft may be stuck or have clogged oil passages.

  • The oil is too thick, causing the passages to become clogged. This can be from the wrong oil or lack of oil changes.

  • The camshaft phaser is stuck in the advanced position.

What are the symptoms of the P0021 code?

  • The ECM will turn on the Check Engine Light.

  • The engine may idle normally but can hesitate or stall on acceleration.

  • A reduction in fuel mileage may happen due to the camshafts not being at an optimal position.

  • The engine emissions may exceed federal levels.

Note: The symptoms may change depending on the camshaft timing positions when the camshaft stopped advancing or retarding.

How does a mechanic diagnose the P0021 code?

  • Visually inspects for damaged wiring or connectors

  • Checks the engine for sludge and for the engine to be full of clean engine oil with the correct viscosity

  • Scans and documents the codes then views the freeze frame data to see when the code was set

  • Clears the OBD-II fault codes and retests the vehicle to see if the P0021 code comes back

  • Performs the manufacturer's pinpoint tests for the P0021 code

Note: The manufacturer's pinpoint test will be different for different engines and year of manufacturer.

Common mistakes when diagnosing the P0021 code

Follow these simple guidelines to help prevent misdiagnosis:

  • Do a visual inspection for problems, like checking to see if all electrical connectors are connected, or harness is damaged.

  • Check engine oil to see if it is full, clean and of the correct viscosity.

  • Verify the failure code is active by clearing and retesting the code.

  • Follow pinpoint tests step-by-step without skipping any steps.

How serious is the P0021 code?

  • The engine may run erratically and have various drive complaints that could cause unsafe driving conditions if the engine hesitates or stalls.

  • The fuel consumption may increase and carbon fouling of engine components may occur.

What repairs can fix the P0021 code?

  • Clearing the Check Engine Light codes and road testing to verify the code

  • Changing the oil and filter to the proper oil viscosity for the engine specifications

  • Repairing or replacing the wiring to the camshaft oil control valve for bank 2 intake camshaft

  • Replacing the camshaft oil control valve for bank 2 intake camshaft

  • Checking the timing chain and camshaft phasers

Additional comments for consideration regarding the P0021 code

The engine oil passages through the camshafts; the oil control valves are of small size and require only the manufacturer's recommended oil viscosity to be used. If the oil is sludged up or an oil with a higher viscosity is in the engine, then it could cause the camshaft VVT to not work as designed.

Need help with a P0021 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

Insurance Requirements for Car Registration in Kentucky
The Kentucky Transportation Cabinet requires that all drivers in Kentucky carry liability automotive insurance, or “financial responsibility” in order to operate a vehicle legally and maintain vehicle...
P2159 OBD-II Trouble Code: Vehicle Speed Sensor B Range/Performance
Diagnostic Trouble Code (DTC): P2159 P2159 code definition Vehicle Speed Sensor B Range/Performance Related Trouble Codes: P2158: Vehicle Speed Sensor B P2160: Vehicle Speed Sensor B Circuit Low P2161:...
P2422 OBD-II Trouble Code: Evaporative Emissions Control System (EVAP) Vent Valve Stuck Closed
Diagnostic Trouble Code (DTC): P2422 P2422 code definition Evaporative Emissions Control System (EVAP) Vent Valve Stuck Closed Related Trouble Codes: P2441: EVAP Vent Valve Stuck Open EVAP trouble...


Related questions

Q: Car won't start after it gets warm.

These are all possible causes for code P0021: Bank 2 camshaft sensor or Bank 2 cam timing solenoid faulty Connector terminal contact is damaged or corroded Wire harness - Check harness for correct voltage Open, short to ground...

Q: my car make rattling noise ,feel like it stops and goes,while driving, and now displays "check engine"

Inasmuch as the check engine light has illuminated, diagnostic trouble codes have been stored in your car's engine computer (PCM) and those codes, once downloaded, will probably reveal at least the general cause of the problem you are having. If...

Q: My truck turns over but won't start.

When a truck won't start, it's usually going to be an ignition or fuel system-related malfunction. The fact that your gas gauge was "ticking" a bit may be an indicator that an electrical problem exists, causing the ignition system to...