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Genel OBD2
🟡 Medium
Genel OBD2
P0400
Exhaust Gas Recirculation Flow Malfunction
The P0400 diagnostic trouble code (DTC) indicates a Exhaust Gas Recirculation Flow Malfunction. This is an emissions-critical fault that prevents the vehicle from effectively reducing airborne pollutants. This anomaly was detected during the ECM's internal diagnostic self-test, indicating that the system is unable to maintain steady-state operation.
Brand
Genel OBD2
Fault Code
P0400
Severity
🟡 Medium
Models
Tüm marka ve modeller
🛠️ Diagnostic Overview
Difficulty Level
🛠️🛠️
Medium (Moderate)
Estimated Time
⏱️ 1-2 Hours
🧰 Required Tools
- ✓ Digital Multimeter
- ✓ Socket Wrench & Hand Tools
- ✓ Smoke Leak Detector / Vacuum Gauge
- ✓ Electrical Contact Cleaner Spray
⚠️ Possible Causes
- Clogged EGR valve
- Faulty EGR solenoid
- Blocked EGR passages
- Vacuum leak
- Faulty DPFE sensor
🔧 Recommended Fixes
- Clean or replace EGR valve
- Clean EGR passages
- Replace EGR solenoid
- Replace DPFE sensor
🚗 Commonly Affected Vehicles
🏭 Genel OBD2 – Other Common Fault Codes