P0012 fault code: what it means

P0012: Bank 1 intake cam timing is more retarded than commanded; the VVT system cannot move the cam to where it should be.

Engine and gearbox (powertrain) · Costly if missed

Usual causes, most likely first

sticking VVT oil control solenoid
low or sludged engine oil
blocked VVT oil feed screen
stretched timing chain

P0012 by make

BMW

Intake cam timing over-retarded (bank 1). The intake VANOS cannot advance the cam as asked.

Usual causes: intake VANOS solenoid clogged or sticking; low or degraded engine oil; stretched timing chain; VANOS adjuster unit fault

Ford

Intake cam timing over-retarded, bank 1: the variable cam timing is further back than commanded. Usually oil related.

Usual causes: low, old or wrong-grade engine oil; VCT solenoid blocked or failed; VCT wiring or loose plug; cam phaser

Hyundai

Intake camshaft timing more retarded than commanded. On Hyundai GDI engines it is an early warning of oil supply problems.

Usual causes: low or dirty engine oil; faulty intake oil control valve; worn timing chain tensioner or stretched chain; sticking intake cam phaser

Kia

Intake camshaft timing over-retarded.

Usual causes: low or dirty engine oil; faulty intake oil control valve; timing chain or tensioner wear; sticking cam phaser

Lexus

Intake cam timing over-retarded (bank 1): the VVT-i cam gear is not moving where the ECM asked.

Usual causes: low or sludged engine oil; sticking VVT oil control valve; faulty VVT-i cam gear/phaser (2GR cold-start bleed-down)

Mazda

Intake cam timing more retarded than target. On SkyActiv-G the electric VVT unit is the usual fault; a loose or jumped timing chain gives the same code.

Usual causes: electric VVT actuator/motor stuck (SkyActiv-G); VVT relay, fuse or wiring fault; loose, stretched or jumped timing chain; low or dirty oil on older oil-fed VVT engines

Mini

Intake cam timing over-retarded. The intake VANOS cannot advance the cam as asked.

Usual causes: intake VANOS solenoid sticking; low or degraded engine oil; stretched timing chain (N12-N18)

Toyota

Intake cam timing over-retarded (bank 1). VVT-i cam gear is not moving to where the ECM asked.

Usual causes: low or sludged engine oil; blocked OCV filter screen or sticking VVT oil control valve; faulty VVT-i cam gear/phaser (2GR-FE cold-start bleed-down); stretched timing chain or cam timing out after chain work

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
Glow plugs (diesel, set of 4)NZ$250–NZ$850 · A$250–A$850

Not sure what P0012 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.