P0253: injection pump fuel metering control A low; identify system and subcode before diagnosis.
Meaning, symptoms, causes and checks
Injection-pump fuel metering control A reports low. The generic cam/rotor/injector wording describes the code family; it does not establish one pump layout or identify a replacement part.
Affected system: Powertrain
Symptoms
- Hard starting or no start if metering is affected.
- Rough idle, stalling or low power; symptoms depend on injection design.
Possible causes
- Damaged connector/wiring, incorrect supply/ground or metering actuator electrical fault.
- Incorrect mechanism/feedback response; evaluate fuel supply and pump by the engine procedure.
What to check
- Identify injection design, subcode and control A in engine documentation; not every vehicle has a rotor sensor.
- Save failure conditions and related pressure, supply or synchronization codes before clearing.
- Inspect pump connector and wiring route; verify electrical supply quality and terminal retention.
- Identify the OEM signal described as low; test supply and ground shorts without assuming low means low fuel flow.
- Perform the OEM metering test and verify the repair; pump replacement/calibration requires complete diagnosis.
Also written as: P0253-00, P025300, PO253 (some scan tools add the fault-type byte, e.g. -00).