EGR · Severity: Moderate
P0402 — Exhaust Gas Recirculation Flow Excessive
The ECU detects more EGR flow than commanded.
Common symptoms
- Rough idle
- Stalling
- Hesitation
Likely causes
- EGR valve stuck open
- Faulty EGR solenoid
- Faulty position sensor
First test to run
At idle, check EGR actual position reads closed; a stuck-open valve shows low MAF and rough idle.
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