P0255 Code Meaning and Next Steps

First checks take 10 to 20 minutes for the first checks. No special tools are usually needed for the first checks.

Can you keep driving?

Stop driving if any of these apply

!The vehicle suddenly runs much worse, loses power sharply, or the check-engine light starts flashing.
!There is a strong smell, smoke, overheating, or any symptom that suggests a real-time safety problem rather than a stored code alone.

If the light is steady and the vehicle still drives normally: Often yes for a short time, but it should not be ignored if drivability changes are obvious.

What to check first

Step-by-step checks

1
Safety first
Work on the fuel system only with the engine off and keep sparks, hot surfaces, and open flames away from the area
2
Free - no tools
Check whether the fault is worse when hot, under load, or after road vibration
3
Basic tool needed
Inspect the connector, harness, and fuel line routing for anything that moves or rubs
4
Basic tool needed
If scan data is available, watch whether commanded fuel delivery drops out while the fault is present
5
Basic tool needed
Look for recent filter or pump work that may have disturbed the wiring or introduced air
6
Basic tool needed
Confirm supply pressure and filter condition so you do not miss a real fueling issue

If the code returns

-If the harness movement changes the fault, repair the wiring before replacing the valve.
-If heat makes it worse, the valve or connector is more suspect than the fuel supply alone.
-If the vehicle also loses power intermittently, confirm whether the supply side is dropping out too.

Background

What this code means

P0255 is a generic OBD-II code for an intermittent fuel metering control circuit fault.

The ECU is seeing the fuel metering system work sometimes and fail at other times. That often comes down to vibration, heat, connector fit, or a valve that is beginning to fail.

Diagnosis

Common causes

Most common

Loose connector or wiring

A connector that shifts with vibration can make the signal come and go.

Common

Metering valve starting to fail

The valve may work cold but drop out after heat soak.

Common

Fuel supply instability

A weak supply can make the metering control loop look intermittent.

Possible

Harness routing or chafing issue

A wire that opens and closes with engine movement can trigger the code.

Avoid these mistakes

What not to do

xDo not replace the pump first if the fault changes when the harness is moved.
xDo not ignore intermittent symptoms just because the vehicle may run normally part of the time.

Parts

Parts that may need replacing

PartTypical costNotes

Fuel metering valve$80-$400Relevant when the valve itself is failing intermittently.

Connector or wiring repair$20-$160Often the best fix when vibration or heat causes the dropout.

Fuel filter or supply-side repair$20-$220Worth checking when the supply side is also unstable.

Related OBD codes

P0252

P0252 means the fuel metering control circuit is not responding properly.

P0253

P0253 means the fuel metering control circuit is reading too low.

P0254

P0254 means the fuel metering control circuit is reading too high.

Source notes

Generic OBD-II (SAE J1979 / ISO 15031-5). P0255 was seeded from dtcdb and then expanded around intermittent fuel metering control faults, especially loose connectors, harness movement, and heat-sensitive valves.

This guide is written as a generic multi-make reference, so bulletin history, sensor locations, and repair order can still change by manufacturer and engine family.

This is generic OBD-II guidance and should not override vehicle-specific service information. Exact diagnosis and repair steps vary by make, engine family, and model year.

Last reviewed: 2026-04-10

Reference: Open reference

P0255 - The Fuel Metering Control Signal Is Intermittent or Unstable