What it means
Fuel metering on channel C of the injection pump is outside the calibrated tolerance. Mechanical wear or pressure regulator drift.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
- The engine or gearbox may go into limp mode
How it works
The injection pump's channel C metering control regulates fuel delivery through the cam, rotor, or injector path specified by the vehicle design. This code sets when channel C metering falls outside its calibrated range, which can reflect pump wear, regulator drift, or a related feedback signal that no longer tracks correctly.
Common causes
Most likely first.
- Internal wear in pump element
- Pressure regulator drift
- Sensor element aged beyond calibration window
Symptoms
- Check-engine light
- Rough running
- Reduced power
How to diagnose it
- Record freeze-frame data and review related fuel-pressure, pump, and injector codes to identify the operating conditions when channel C left its expected range.
- Inspect channel C wiring and connectors for corrosion, looseness, chafing, or contamination that could distort control or feedback.
- Compare commanded and actual channel C metering and fuel-pressure data with the manufacturer's specifications under the stated test conditions.
- Check the pressure regulator and relevant feedback sensor readings for drift or instability using the manufacturer's procedure.
- If electrical and feedback checks pass, test the injection pump for internal wear affecting channel C delivery.
Common fixes
- Repair poor channel C connector contact or damaged wiring.
- Replace a feedback sensor only if testing confirms its readings have drifted out of specification.
- Repair or replace a pressure regulator that fails its specified test.
- Repair or replace the injection pump if channel C internal wear is confirmed.
Can I keep driving?
Do not continue driving if the engine stalls, runs very roughly, or has substantially reduced power; fuel delivery could deteriorate further. If it remains stable, keep any trip short and avoid heavy loads until diagnosed.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.