P0251 Code: Injection Pump Fuel Metering Control A Malfunction
🟠 Moderate severity · drivable
Drivable only if the engine runs smoothly — a bad fuel metering control can cause hard starting or stalling, so fix it soon.
What P0251 means
This is a diesel engine code. The fuel metering control on the injection pump, which adjusts how much fuel the pump delivers, has an electrical fault. If it can't meter fuel correctly, the engine gets the wrong amount of fuel and runs poorly.
Symptoms
- Check engine light is on
- Hard starting or no-start
- Rough running or stalling
- Loss of power
- Black or white exhaust smoke
Common causes
- most common: Faulty fuel metering solenoid or actuator on the pump
- common: Damaged wiring or loose connector to the pump
- less common: Internal injection pump failure
How to fix it
| Fix | DIY? | Typical cost |
|---|---|---|
| Inspect and repair the pump wiring and connector | Mechanic | $50–200 |
| Replace the fuel metering solenoid or actuator | Mechanic | $100–300 |
| Rebuild or replace the injection pump | Mechanic | $800–2000 |
Frequently asked questions
Can I drive with a P0251 code?
Only if the engine starts and runs smoothly, and with caution — it could stall or fail to restart. Fix it soon.
What is the most common cause of P0251?
A faulty fuel metering solenoid or actuator on the injection pump, or wiring problems.
How much does it cost to fix a P0251?
Usually $100–300 for a new metering solenoid, or $800–2000 if the injection pump is rebuilt or replaced.
Related codes
P0252
P0252 Code: Injection Pump Fuel Metering Control A Out of Range
P0253P0253 Code: Injection Pump Fuel Metering Control A Signal Low
P0230P0230 Code: Fuel Pump Primary Circuit Malfunction
Updated 2026-08. This page is informational and not a substitute for professional diagnosis.