P0404 fault code: Exhaust Gas Recirculation Control Circuit Range/Performance

P0404 means “Exhaust Gas Recirculation Control Circuit Range/Performance” — an auxiliary emission controls fault in the powertrain.

Can I DIY?

Professional-only boundary. Confirm P0404 on a scanner; do not remove or clean the EGR valve from 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 P0404

Do not drive. The EGR valve’s reported position or its control signal is outside the expected range. This is not a flow code (P0401/P0402) or an open-circuit code (P0403), and it does not authorise cleaning the valve.

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

  • Exhaust Gas Recirculation Control Circuit Range/Performance: Registration number
  • Exhaust Gas Recirculation Control Circuit Range/Performance: Exact code P0404 and any P0401, P0402 or P0403 companions
  • Exhaust Gas Recirculation Control Circuit Range/Performance: Whether the engine management light is on
  • Exhaust Gas Recirculation Control Circuit Range/Performance: Any EGR position or duty readings if the scanner showed them
  • Exhaust Gas Recirculation Control Circuit Range/Performance: Any exhaust smell in the cabin
Hot systems

Never open a hot coolant cap — pressure can scald you. Exhaust and catalytic converter get hot enough to burn and ignite debris. Stay clear of electric fans; they can run after shut-off.

P04xxAuxiliary emission controls
MOT fail riskif the warning light stays on

What does P0404 mean?

P0404 is a generic (SAE standard) powertrain code reported by your car’s engine control unit. It sits in the P04xx block, which covers auxiliary emission controls. The stored description is “Exhaust Gas Recirculation Control Circuit Range/Performance”. The code itself tells you which circuit or system tripped the fault — not always the exact part that failed.

Will P0404 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

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.
P0400Exhaust Gas Recirculation Flow P0401Exhaust Gas Recirculation Flow Insufficient Detected P0402Exhaust Gas Recirculation Flow Excessive Detected P0403Exhaust Gas Recirculation Control Circuit P0405Exhaust Gas Recirculation Sensor 'A' Circuit Low P0406Exhaust Gas Recirculation Sensor 'A' Circuit High P0407Exhaust Gas Recirculation Sensor 'B' Circuit Low P0408Exhaust Gas Recirculation Sensor 'B' Circuit High

P0404 — quick answers

Is it safe to drive with P0404?

Do not drive. Driveability guidance is not available for this code — treat as do not drive until checked. Do not borrow drive advice from EGR flow codes.

Will P0404 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.