Fault code P1403 – a step-by-step guide to diagnosing and fixing it

Error code P1403 is displayed and the check engine light is on - what does this mean?

The DTC P1403 is recognized by the OBD system if there is a problem with the exhaust gas recirculation valve (EGR valve) or its control circuit. This manufacturer-specific error code mainly affects the exhaust gas recirculation system and can have different meanings for different vehicle brands.

What causes can this error code have?

• Defective EGR valve
• Blocked EGR ducts due to soot deposits
• Damaged vacuum hose system
• Faulty EGR valve control
• Defective EGR position sensor
• Loose or corroded plug connections
• Defective engine control unit software
• Dirty or defective vacuum pump

What symptoms occur in parallel with fault code P1403?

• Unsteady idling: The engine runs unstable or unevenly when idling
• Increased exhaust values: Deteriorated emission values during the emissions test
• Loss of power: Reduced engine power, especially at low engine speeds
• Knocking noises: Metallic knocking noises from the engine compartment
• Black smoke: Dark exhaust fumes from the exhaust pipe
• Increased fuel consumption: Noticeable increase in fuel consumption

How can I fix the problem with error code P1403?

• Repairing the P1403 error code requires a systematic approach to identifying and eliminating the cause.
• Remove EGR valve, clean thoroughly or replace completely if defective, then check function with diagnostic device
• Remove soot deposits from all EGR ducts and lines with a special cleaner and check patency
• Check vacuum hoses for cracks and leaks, replace damaged hoses and tighten connections
• Check the EGR position sensor electrically, replace if it fails and carry out basic adjustment with diagnostic device
• Check all electrical connections on the EGR system for corrosion and tight fit, repair defective connectors
• Check engine control unit software for updates and update if necessary