P0103 fault code: Mass or Volume Air Flow Circuit High Input

P0103 means “Mass or Volume Air Flow Circuit High Input” — a fuel and air metering fault in the powertrain.

Can I DIY?

Professional-only boundary. Read P0103 only; a high air-flow input is not a published clean-or-replace job on this page.

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 P0103

Do not drive. The air-flow meter circuit is reporting a high input, as if more air were arriving than the engine should be drawing at that moment.

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

  • Mass or Volume Air Flow Circuit High Input: Registration number
  • Mass or Volume Air Flow Circuit High Input: Exact code P0103 and freeze-frame rpm or load if shown
  • Mass or Volume Air Flow Circuit High Input: Companion misfire or fuel-trim codes
  • Mass or Volume Air Flow Circuit High Input: Whether the fault set at idle, on pull-away, or at motorway speed
P01xxFuel and air metering
MOT fail riskif the warning light stays on

What does P0103 mean?

P0103 is a generic (SAE standard) powertrain code reported by your car’s engine control unit. It sits in the P01xx block, which covers fuel and air metering. The stored description is “Mass or Volume Air Flow Circuit High Input”. The code itself tells you which circuit or system tripped the fault — not always the exact part that failed.

Will P0103 fail an MOT?

An illuminated engine management light is a Major defect at MOT until the fault is repaired and the lamp stays off. P0103 is a high air-flow circuit input, not a named MOT item.

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.
P0100Mass or Volume Air Flow Circuit P0101Mass or Volume Air Flow Circuit Range/Performance P0102Mass or Volume Air Flow Circuit Low Input P0104Mass or Volume Air Flow Circuit Intermittent P0105Manifold Absolute Pressure/Barometric Pressure Circuit P0106Manifold Absolute Pressure/Barometric Pressure Circuit Range/Performance P0107Manifold Absolute Pressure/Barometric Pressure Circuit Low Input P0108Manifold Absolute Pressure/Barometric Pressure Circuit High Input

P0103 — quick answers

Is it safe to drive with P0103?

Do not drive. We have no verified driving guidance for P0103 — treat as do not drive until checked. A high input is not a DIY cue to blow the sensor with a compressor.

Will P0103 fail my MOT?

An illuminated engine management light is a Major defect at MOT until the fault is repaired and the lamp stays off. P0103 is a high air-flow circuit input, not a named MOT item.

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.