What it means
The control module detected an intermittent fault in the diesel intake air flow control circuit.
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 control actuator and valve regulate airflow into the engine, while the control module monitors their response. This code sets when the circuit or actuator response is inconsistent, so a fault may appear only as the wiring moves or the valve sticks during operation.
Common causes
Most likely first.
- Carbon buildup or broken return spring
- Carbon or debris buildup preventing free movement
- Component wear with age - mechanical play
Symptoms
- Check-engine light on
- Intermittent loss of power or hesitation
- Rough or unstable idle
- Increased fuel consumption
How to diagnose it
- Save freeze-frame data and check related codes and available command or position data to identify when the intermittent fault occurred.
- Inspect the actuator connector and harness for loose terminals, corrosion, chafing, or damage that could interrupt the signal intermittently.
- With the engine off, inspect the valve, linkage, and return mechanism for carbon buildup, binding, excessive play, or a damaged spring.
- Use the manufacturer’s scan-tool procedure to command valve movement and watch for hesitation or position feedback that drops out.
- If the fault persists, test the wiring for intermittent opens and check actuator and position feedback using the manufacturer’s procedure.
Common fixes
- Secure a loose actuator connector and repair damaged or chafed wiring.
- Clean carbon or debris from the valve using the vehicle’s approved procedure.
- Repair a sticking or damaged linkage or return mechanism.
- Replace a worn actuator or position sensor if testing confirms intermittent operation.
Can I keep driving?
Driving may be possible while the engine runs normally, but intermittent hesitation or power loss can return without warning. Avoid demanding trips or heavy loads until diagnosed, and stop if the engine stalls or power loss makes driving unsafe.
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.