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P0252 — Injection Pump Fuel Metering Control Rangeperformance Camrotorinjector

Generic OBD-II · all makesPowertrain (engine & transmission)

P0252 indicates that the engine control module has detected the fuel injection pump's metering control circuit is operating outside its expected range. This usually means the pump cannot maintain the correct fuel quantity or timing for proper combustion.

Symptoms

What causes it — most likely first

1. Faulty injection pump metering valve or internal pump failure

The metering valve inside the high‑pressure fuel pump can stick, wear, or fail electrically, causing the pump to deliver incorrect fuel amounts and triggering the range‑performance code.

2. Wiring or connector issues to the injection pump

Corrosion, chafed wires, loose pins, or water intrusion in the pump’s harness can interrupt the control signal, making the ECM see an out‑of‑range condition.

3. Defective fuel pressure sensor (rail or pump side)

If the pressure sensor feeds incorrect data to the ECM, the controller may command the pump outside its normal operating window, setting P0252.

4. Inadequate fuel supply (clogged filter, weak lift pump, air in system)

Low inlet pressure or fuel starvation prevents the injection pump from building proper pressure, which the ECM interprets as a metering control fault.

5. Contaminated or incorrect fuel

Water, debris, or the wrong fuel grade can affect pump internals and sensor readings, leading to performance out‑of‑range conditions.

6. PCM/ECM malfunction (rare)

While the ECM is sometimes blamed, a genuine controller failure is uncommon for P0252 and should only be considered after all pump, wiring, sensor, and fuel‑system checks are normal.

How it's diagnosed

  1. Scan for all stored codes and note any related fuel‑pressure or sensor codes.
  2. Verify fuel level, check the fuel filter, and inspect for water or contaminants in the fuel.
  3. Measure actual fuel rail/injection pump pressure with a gauge and compare to specifications.
  4. Visually inspect the injection pump harness and connectors for damage, corrosion, or loose connections; repair as needed.
  5. Command the injection pump metering valve via a scan tool (if supported) and observe response; abnormal behavior points to pump or valve failure.
  6. If pressure, wiring, and sensor tests are normal, consider a PCM/ECM test or substitution as a last resort.

Code facts & related codes

SystemPowertrain (engine & transmission)
StandardizationSAE generic — identical on every make
Related codesP0250 — Turbochargersupercharger Wastegate ActP0251 — Injection Pump Fuel Metering Control CP0253 — Injection Pump Fuel Metering Control LP0254 — Injection Pump Fuel Metering Control HP0255 — Injection Pump Fuel Metering Control IP0256 — Injection Pump Fuel Metering Control B

Frequently asked

Is replacing the PCM/ECM a common fix for P0252?

No. The PCM is rarely at fault for this code; most cases are due to the injection pump, its wiring, fuel pressure sensor, or fuel supply issues. PCM replacement should only be considered after those components have been verified good.

Can I continue driving with a P0252 code?

Driving may be possible for short distances, but the engine may run poorly, lose power, or stall. Continued operation risks further damage to the injection pump or other fuel‑system components, so prompt diagnosis is advised.

After fixing the cause, will the code clear automatically?

Once the underlying issue is repaired, the code can be cleared with a scan tool. If the fault is resolved, the code should not return; if it does, the repair was incomplete or another fault exists.

Do I need to replace the entire injection pump if the metering valve is faulty?

It depends on the pump design. Some pumps allow the metering valve or its actuator to be serviced separately; others require pump replacement. Consult the vehicle’s service manual for the specific repair procedure.