P0255

Injection Pump Fuel Metering Control A Intermittent (Cam/Rotor/Injector)

Fuel injection (diesel) Generic OBD-II High

What it means

P0255 means the ECM sees an intermittent fault in the "A" fuel-metering control of the diesel injection pump — the valve that regulates how much fuel the pump delivers. Because that control drops in and out, the engine can run rough, lose power, stall, or become hard to start. Loose wiring and a failing metering valve are common causes; the pump itself is checked last.

High

Can I keep driving? Drive with caution — an intermittent metering-control fault can cause sudden stalling, hard starting, or reduced power. Diagnose it before long trips.

Real-world scan data

Seen in

293

scans in the past year

Found in

0.1%

of scans

0.1%

of scans that found faults

Appears alongside · share of P0255 scans

P1646in 67.2% of scans

P0489in 34.1% of scans

P0704in 30.7% of scans

Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.

Common symptoms

What you'll notice

Check-engine light on
Hard starting or intermittent no-start
Rough running or stalling
Reduced power and hesitation

Common causes

Most likely first

Loose, corroded, or intermittent wiring/connector at the fuel metering control (circuit 'A')Likely
Faulty fuel metering control valve/actuator on the injection pumpCommon
Worn or failing injection pumpCommon
Failed engine control module (ECM)Less often

How to diagnose & fix

Work through it in order

Read freeze-frame data, then wiggle-test the metering-control wiring and connector while watching for signal dropouts.
Inspect and reseat the connector; clean corrosion and repair damaged wiring.
Test the fuel metering control valve/actuator resistance and command it with a scan tool.
Check injection-pump fuel pressure/delivery against spec.
Replace the metering control valve or injection pump only after wiring checks out; suspect the ECM last.

FAQ

Quick answers

Is it safe to drive with P0255?+

Not for long trips — the fault is intermittent and can cause stalling or a no-restart. Get it diagnosed before relying on the vehicle.

Can I just clear P0255?+

It clears, but an intermittent metering-control fault returns once the loose wiring or failing valve acts up again. Fix the cause.

Read & clear P0255 yourself

Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.

▶ Get it on Google Play

✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX