OBD-II Generic Error Code P0021: How to Fix It

Q: Can I drive with code P0021?

It is not recommended to drive long distances. The over-advanced timing can cause engine knocking, reduced performance, and possible damage. Have it diagnosed promptly.

Q: What does bank 2 mean?

Bank 2 refers to the side of the engine that does not contain cylinder #1. In V6/V8 engines, bank 1 is typically the driver’s side (left) and bank 2 is passenger’s side (right). Check your vehicle's repair manual for confirmation.

Q: Will an oil change fix P0021?

Sometimes. If the VVT system is sluggish due to dirty or low oil, a fresh oil change with the correct grade can restore proper operation. It's a good first step.

Q: Can a bad VVT solenoid cause P0021?

Yes, a stuck or failed VVT solenoid is a common cause. It controls oil flow to the camshaft phaser to adjust timing.

Q: How much does it cost to fix P0021?

DIY cost for a VVT solenoid is $50-$150. Professional diagnosis and repair can range from $200 for a solenoid replacement to $1000+ for timing chain repairs.

Abstract

Error code P0021 indicates that the engine control module (ECM) has detected that the camshaft timing is over-advanced (ahead of where it should be) on the bank 2 intake camshaft. This typically points to an issue with the variable valve timing (VVT) system, such as a faulty VVT solenoid, oil flow problem, or timing chain stretch.