What it means
Air flow through diesel intake throttle A is higher than the commanded set point — flap leaking past the seat or stuck partly open.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
The diesel intake air flow A control system uses a throttle plate to regulate airflow through intake passage A. P02EC sets when measured airflow is higher than the module's commanded target, which can happen if the plate leaks or sticks partly open, or if the airflow sensor or its wiring reports too much air.
Common causes
Most likely first.
- Intake throttle plate not closing fully or leaking air
- Throttle plate or actuator sticking open
- Airflow sensor or its wiring reporting an incorrect high reading
Symptoms
- Reduced engine power or uneven acceleration
- Rough engine response
- Poorer fuel economy
How to diagnose it
- Review freeze-frame and live commanded A throttle position alongside measured airflow to confirm that airflow is high when the plate should be more closed.
- Inspect the A throttle plate and actuator for carbon, damage, or a mechanism that does not return fully toward its commanded position.
- Check the intake path around throttle A for leakage or a plate that fails to seal as intended.
- Inspect the airflow sensor connector and wiring for damage or poor connections that could create a falsely high reading.
- Compare airflow readings and A throttle response with the manufacturer's diagnostic procedure to separate a mechanical leak from a sensor or circuit fault.
Common fixes
- Clean carbon or debris preventing the A throttle plate from closing fully.
- Repair a sticking A throttle plate, actuator, or linkage.
- Repair an intake leak at or around throttle A.
- Repair the airflow sensor wiring or replace the sensor if its reading is inaccurate.
Can I keep driving?
If the engine response is stable, keep trips short and avoid hard acceleration while the high airflow condition is diagnosed. Uneven acceleration or reduced power can worsen, so stop if the engine stalls or becomes difficult to control in traffic.
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.