Fault code P1404 – a step-by-step guide to diagnosing and fixing it

Error code P1404 is displayed and the check engine light is on - what does this mean?

The OBD/EOBD system has detected a fault in the exhaust gas recirculation system (EGR), specifically a position error in the EGR valve. This manufacturer-specific DTC P1404 indicates that the EGR valve has not reached the expected position or is sending incorrect feedback to the control unit.

What causes can this error code have?

• Defective EGR valve
• Dirty or blocked EGR valve
• Damaged EGR valve position sensor
• Defective wiring to the EGR system
• Loose or corroded plug connections
• Blocked EGR lines
• Faulty vacuum hoses
• Defective engine control unit
• Dirty EGR cooler

What symptoms occur in parallel with fault code P1404?

• Uneven idling: The engine runs unevenly or stutters when idling
• Loss of power: Reduced engine power, especially at low engine speeds
• Increased fuel consumption: The engine requires more fuel than usual
• Black smoke: Dark exhaust fumes from the exhaust pipe
• Knocking noises: Unusual engine noises during acceleration
• Starting problems: Difficulty starting the engine

How to fix the problem of error code P1404?

• The repair requires a systematic approach to identify and eliminate the cause.
• Clean the EGR valve: Remove the EGR valve and clean it thoroughly with special EGR cleaner to remove carbon deposits
• Replace EGR valve: Replace a defective EGR valve with a new original part or high-quality replacement part
• Check and replace position sensor: Test the EGR position sensor with a multimeter and replace if defective
• Repair wiring: Check all cables to the EGR system for damage and repair or replace defective cables
• Clean plug connections: Clean all plugs on the EGR system and treat them with contact spray to prevent corrosion
• Clean the EGR pipes: Flush the EGR pipes with a suitable cleaner to remove blockages