Mazda P0011

Intake cam over-advanced on Mazda Skyactiv-G — the Oil Control Valve and timing chain wear are the usual causes.

Mazda P0011 — Intake cam over-advanced on Mazda Skyactiv-G — the Oil Control Valve and timing chain wear are the usual causes. Typical UK independent garage cost: £180–£1100.

What actually causes P0011 on a Mazda

Skyactiv engines run a high 13:1–14:1 compression ratio and rely on precise VVT timing. P0011 on these is most often a sticky intake OCV solenoid (oil varnish from extended drain intervals) or, on higher-mileage cars, timing chain stretch. We also see it after a dealer oil change using the wrong viscosity — Skyactiv wants 0W-20, not 5W-30.

Mazda engines that log P0011

• Skyactiv-G 2.0 / 2.5 (Mazda 3, 6, CX-5, CX-30)
• 1.5 Skyactiv-G (Mazda 2, CX-3, Mazda 3)

How we diagnose P0011 on a Mazda

1. Scan tool: read intake cam advance error at warm idle — >5° suggests valve or chain fault
2. Remove intake OCV (top of cam cover, front), clean filter screen and inspect for varnish
3. Test OCV resistance against Mazda spec (~7Ω cold) — out of spec equals replace
4. If solenoid clean and in spec, inspect chain for stretch via cam/crank correlation in live data
5. Check oil grade on cap and service history — Skyactiv is fussy about 0W-20

The common misdiagnosis to avoid

Don't accept a chain replacement quote on a Skyactiv under 80k miles without first proving the OCV — a £90 solenoid swap cures most P0011 codes on Skyactiv 2.0/2.5.

Mazda P0011 repair cost in the UK

Expect £180–£1100 including parts and labour at an independent garage. Main-dealer quotes on Mazda are usually higher for the same job, and the spread exists because the cheap cause and the expensive cause throw the same code — pay for the diagnosis before you pay for parts.

Bob's workshop tip

Skyactiv DI engines also suffer carbon build-up on intake valves which can throw VVT learning off — if you're already in there for a chain, a walnut blast at the same time saves a future job.

Codes usually seen alongside P0011 on Mazda

• P0014
• P0016
• P0021

Symptoms drivers report with P0011

• Engine rattles like a 'bag of nails' for 3 seconds on a cold start.
• The car felt fine on the motorway, but now it stalls every time I stop at a roundabout.
• Noticeable 'flat spot' or hesitation when trying to overtake in 3rd gear.
• Lumpy, hunting idle that makes the gearstick vibrate.
• Fuel economy has tanked—getting about 10mpg less than usual.

Repairs that clear P0011

• Engine flush and oil change
• Replace VVT solenoid
• Replace cam phaser if needed

For the generic, all-makes explanation of this code — meaning, every known cause and UK cost bands — see our P0011 guide.