P0402moderate severityPowertrain
EGR Flow Excessive Detected
on 2015 Audi A3 2.0L Turbo I4 · AWD
What this code means
The EGR system is flowing too much exhaust gas.
Symptoms
- Check Engine Light
- Rough idle
- Stalling
- Surging
- Poor acceleration
Common causes
- EGR valve stuck open
- Faulty EGR solenoid
- Vacuum leak to EGR valve
- Faulty DPFE sensor reading low
Diagnostic steps
- Check EGR valve for stuck-open condition
- Test EGR solenoid
- Check vacuum lines
- Test DPFE/position sensor
Repair notes
Replace EGR valve if stuck open. Repair vacuum lines.
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