P0270 fault code: Cylinder 4 Injector Circuit Low

Last updated · OBDCode UK editorial

Can I drive with P0270? — Limited driving

Limited driving: a smooth four-cylinder or V-engine may be driven carefully to a garage. Stop if cylinder 4 drops out under load or the lamp flashes.

P0270 means “Cylinder 4 Injector Circuit Low” — a fuel and injector circuits fault in the powertrain. Limited driving. The fourth cylinder's injector circuit is under the low threshold. On a four-cylinder engine this is the last injector; on a V8 it is one of eight — either way the fuel is high pressure.

Can I DIY?

Do not DIY this repair. We do not publish DIY repair or strip-down steps for this code on this page. Read codes and observe only; leave the repair to a qualified garage.

Do not DIY this repairDIY boundary
ToolsSpecialist tools or workshop equipment — typically a professional garage job.

This fault is in the professional-only category. We do not publish strip-down or fitting steps on this page. Use a qualified garage.

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.

P02xxFuel and injector circuits
MOT fail riskif the warning light stays on

What does P0270 mean?

P0270 is a generic (SAE standard) powertrain code reported by your car’s engine control unit. It sits in the P02xx block, which covers fuel and injector circuits. The stored description is “Cylinder 4 Injector Circuit Low”. The code itself tells you which circuit or system tripped the fault — not always the exact part that failed.

Will P0270 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.

What the MOT data says

No MOT certificate item corresponds to this code; MOT outcome data cannot be shown.

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.
P0200Injector Circuit/Open P0201Injector Circuit/Open - Cylinder 1 P0202Injector Circuit/Open - Cylinder 2 P0203Injector Circuit/Open - Cylinder 3 P0204Injector Circuit/Open - Cylinder 4 P0205Injector Circuit/Open - Cylinder 5 P0206Injector Circuit/Open - Cylinder 6 P0207Injector Circuit/Open - Cylinder 7

P0270 — quick answers

Is it safe to drive with P0270?

Limited driving. Limited driving: a smooth four-cylinder or V-engine may be driven carefully to a garage. Stop if cylinder 4 drops out under load or the lamp flashes.

Can I fix P0270 myself?

Do not DIY this repair. We do not publish DIY repair or strip-down steps for this code on this page. Read codes and observe only; leave the repair to a qualified garage. Specialist tools or workshop equipment — typically a professional garage job.

Will P0270 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.