P0094 fault code: Fuel System Leak Detected - Small Leak

P0094 means “Fuel System Leak Detected - Small Leak” — a fuel and air metering fault in the powertrain.

Can I DIY?

Professional-only boundary. You may confirm P0094 on a scanner; finding and sealing a fuel leak is garage work.

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 P0094

Do not drive. A small fuel-system leak has been detected. A slow weep can still wet the underbody or smell in the cabin; it is not automatically a loose filler cap.

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

  • Fuel System Leak Detected - Small Leak: Registration number
  • Fuel System Leak Detected - Small Leak: Exact code P0094 and companion codes
  • Fuel System Leak Detected - Small Leak: Whether the smell is strongest after filling up
  • Fuel System Leak Detected - Small Leak: Any drip, stain, or damp fuel-line area you noticed without crawling under the car
P00xxFuel and air metering
MOT fail riskif the warning light stays on

What does P0094 mean?

P0094 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 “Fuel System Leak Detected - Small Leak”. The code itself tells you which circuit or system tripped the fault — not always the exact part that failed.

Will P0094 fail an MOT?

An illuminated engine management light is a Major defect at MOT until the fault is repaired and the lamp stays off. P0094 names a small fuel leak to the computer; MOT testers still judge visible leaks on their own rules.

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

P0094 — quick answers

Is it safe to drive with P0094?

Do not drive. We have no verified driving guidance for P0094 — treat as do not drive until checked. A 'small' leak is still fuel outside the sealed system; do not ignore a smell.

Will P0094 fail my MOT?

An illuminated engine management light is a Major defect at MOT until the fault is repaired and the lamp stays off. P0094 names a small fuel leak to the computer; MOT testers still judge visible leaks on their own rules.

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.