P0314 fault code: Single Cylinder Misfire (Cylinder not Specified)

P0314 means “Single Cylinder Misfire (Cylinder not Specified)” — an ignition system and misfire fault in the powertrain.

Can I DIY?

Professional-only boundary. P0314 does not name the cylinder. Do not guess which coil to swap. Confirm the code and book a garage.

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 P0314

Do not drive. A single-cylinder misfire was detected but the computer did not name the cylinder. You cannot tell from this code which coil or injector to touch.

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

  • Single Cylinder Misfire (Cylinder not Specified): Registration number
  • Single Cylinder Misfire (Cylinder not Specified): Exact code P0314 and any companion misfire or fuel codes
  • Single Cylinder Misfire (Cylinder not Specified): Whether the engine management light is flashing
  • Single Cylinder Misfire (Cylinder not Specified): Whether freeze-frame data was captured on your scanner
P03xxIgnition system and misfire
MOT fail riskif the warning light stays on

What does P0314 mean?

P0314 is a generic (SAE standard) powertrain code reported by your car’s engine control unit. It sits in the P03xx block, which covers ignition system and misfire. The stored description is “Single Cylinder Misfire (Cylinder not Specified)”. The code itself tells you which circuit or system tripped the fault — not always the exact part that failed.

Will P0314 fail an MOT?

An illuminated engine management light is a Major defect at MOT (automatic fail) until the fault is repaired and the light stays off.

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

P0314 — quick answers

Is it safe to drive with P0314?

Do not drive. Driveability guidance is not available for this code — treat as do not drive until checked.

Will P0314 fail my MOT?

An illuminated engine management light is a Major defect at MOT (automatic fail) until the fault is repaired and the light stays off.

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.