P0255: Injection Pump Fuel Metering Control A Intermittent (Cam/Rotor/Injector)

These codes cover the electrically controlled fuel metering actuator on a diesel injection pump – on common rail usually an inlet metering valve on the high-pressure pump that sets how much fuel is compressed. P0255 reports brief open or short circuits in the actuator A circuit that come and go – typically a loose contact or a wire breaking under vibration. No manufacturer using it with exactly this meaning was found; a Ram 6.7 Cummins code list names it as a circuit performance fault instead. The description follows CARB's continuous circuit monitoring requirement and the documented A siblings.

Medium severity. Can I keep driving?Drive as little as possible and go to a repair shop. If you smell fuel or the engine is shaking badly, do not keep driving.

Symptoms

Check engine light (often goes out again)
Brief jerking or power dips
Occasional limp mode

Most likely causes

Loose contact or corrosion at the metering actuator connector
Harness chafing intermittently (vibration)
Actuator coil with a temperature-dependent fault
Engine module

What to check, in order

Start with the simplest. You can tick off each step.

Check the connector and wiring of the injector indicated
Gently move the wiring with the engine running and watch whether the reading changes.
Measure the resistance and compare it with the manufacturer's specification
Check the control signal with an oscilloscope; on direct injection or diesel engines, leave this to a repair shop because of the high voltages
On diesels, check the per-cylinder injection corrections

Good to know

Repair difficulty: medium
It can trigger limp mode.
It affects emissions.

What each character of P0255 means

P: Powertrain: engine and transmission
0: Generic code: same on every make
2: Fuel injection
55: Specific fault in that system

Frequently asked questions

Can I keep driving with code P0255?

Drive as little as possible and go to a repair shop. If you smell fuel or the engine is shaking badly, do not keep driving.

What causes code P0255?

The most common causes are: loose contact or corrosion at the metering actuator connector; harness chafing intermittently (vibration); actuator coil with a temperature-dependent fault.

Related codes

Sources

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.