P0012 fault code: 'A' Camshaft Position - Timing Over-Retarded

P0012 means “'A' Camshaft Position - Timing Over-Retarded” — a fuel and air metering fault in the powertrain.

Can I DIY?

Professional-only boundary. Do not drop the oil and yank the VVT solenoid for P0012.

Do not DIYReviewed page boundary
ToolsSpecialist equipment

This is the conservative boundary from the reviewed code record. This page has no frozen site-wide safety grade, so it does not publish a repair route.

What to tell the garage about P0012

Do not drive until checked. Camshaft A is later than the computer commanded — timing is over-retarded on that cam (P001x bank). Variable-cam control has not brought cam A back on target.

Take these reviewed, code-specific details with you. They help the garage confirm the fault without turning this page into a repair procedure.

  • 'A' Camshaft Position - Timing Over-Retarded: Registration number
  • 'A' Camshaft Position - Timing Over-Retarded: Exact code P0012 and any companion codes from the same scan
  • 'A' Camshaft Position - Timing Over-Retarded: Whether the engine management light is steady or flashing
  • 'A' Camshaft Position - Timing Over-Retarded: Oil grade last used and any recent oil-change interval
P00xxFuel and air metering
MOT fail riskif the warning light stays on

What does P0012 mean?

P0012 is a generic (SAE standard) powertrain code reported by your car’s engine control unit. It sits in the P00xx block, which covers fuel and air metering. The stored description is “'A' Camshaft Position - Timing Over-Retarded”. The code itself tells you which circuit or system tripped the fault — not always the exact part that failed.

Will P0012 fail an MOT?

DVSA MOT inspection fails a lit engine management light as Major. P0012 is an over-retarded cam-A timing result, not an oxygen-sensor heater or turbo-bypass code.

Before booking your test, check what usually fails on your car: see our MOT pass rates by make and model, built from 33.1 million DVSA tests.

Related guides

Car diagnostic test cost: compare the scopeUK booking marketplaces currently publish diagnostic averages of about £52–£65. Engine management light on: steady or flashing?A steady engine management light means the computer has stored a fault. Drive with caution and get the code read. A flashing light is different — stop when it is safe.
P0001Fuel Volume Regulator Control Circuit/Open P0002Fuel Volume Regulator Control Circuit Range/Performance P0003Fuel Volume Regulator Control Circuit Low P0004Fuel Volume Regulator Control Circuit High P0005Fuel Shutoff Valve 'A' Control Circuit/Open P0006Fuel Shutoff Valve 'A' Control Circuit Low P0007Fuel Shutoff Valve 'A' Control Circuit High P0008Engine Position System Performance

P0012 — quick answers

Is it safe to drive with P0012?

Do not drive until checked. We have no verified driving guidance for P0012. Treat as do not drive until checked. Over-retarded cam A is not a licence to remove the VVT solenoid.

Will P0012 fail my MOT?

DVSA MOT inspection fails a lit engine management light as Major. P0012 is an over-retarded cam-A timing result, not an oxygen-sensor heater or turbo-bypass code.

Fault-code identifiers are standard diagnostic facts. Their explanations and diagnostic guidance on this site are original editorial summaries, not reproduced SAE wording. MOT defect rules reflect the DVSA MOT inspection manual (2026). This page is general guidance for UK drivers, not a substitute for a professional diagnosis.