P0021 fault code: what it means

P0021: Bank 2 intake cam timing is over-advanced or the bank 2 VVT system is not following commands (V engines).

Engine and gearbox (powertrain) · Costly if missed

Usual causes, most likely first

low or dirty engine oil
sticking bank 2 VVT oil control solenoid
stretched timing chain
worn bank 2 cam phaser

P0021 by make

Jeep

Intake cam timing over-advanced (bank 2) on V6 Jeeps.

Usual causes: sticking bank 2 oil control solenoid; low or old oil; worn cam phaser

Nissan

Intake cam timing bank 2 over-advanced (V6 VQ engines). Often logged with P0011.

Usual causes: low or dirty engine oil; bank 2 intake valve timing solenoid sticking; timing chain stretch or guide wear

Subaru

Intake cam timing (AVCS) on bank 2 (left/driver head) is more advanced than commanded. Swapping the two oil control valves shows if the valve is the fault.

Usual causes: low or dirty engine oil (FB25 oil use is a common trigger); sticking or sludged AVCS oil control valve; blocked oil control valve filter screen; stretched timing chain on FB/FA engines

What the repair usually costs

A/C compressor replace incl. drier and flush (European)NZ$1,560–NZ$3,200 · A$1,490–A$3,050
Timing chain, tensioner and guides (4-cylinder)NZ$1,120–NZ$2,530 · A$1,160–A$2,570
Timing chains and tensioners (V6 / V8)NZ$1,890–NZ$4,080 · A$1,920–A$4,110

Not sure what P0021 means on your car? Ask Credov.

Before you clear it

Write the code down or photograph the scanner first. A code that comes straight back after clearing points to a fault that is still there. A car whose codes were cleared just before you arrived may be hiding one: the scanner's readiness monitors show "not ready" for a while after codes are cleared.

Researched by Credov from manufacturer and workshop sources. A fault code points to where a fault may be; a workshop confirms it with a diagnosis. Browse all fault codes.