OBD · Emissions control

P0403 EGR control circuit

Monitor

What this code means

P0403 is a generic OBD code shared by all manufacturers since 2001 for petrol and 2004 for diesel. It relates to: emissions control. The code tells you what the ECU measured as abnormal, not necessarily which part to replace.

Severity: Monitor. You can drive normally but get it checked in the coming weeks. It may fail an MOT or roadworthiness test.

Most common causes

  1. Clogged EGR valve#1
    Garage price: EGR valve £275 – £740

Cost of related repairs

Independent garageMain dealer
EGR valve£275 – £740£360 – £1,145

How to read this code

An OBD scanner plugged into the 16-pin socket under the steering wheel reads and clears codes. Bluetooth models cost £20 to £40. Clearing a code without fixing the fault is pointless: it comes back.

Related problems

Car judders when acceleratingLoss of power and limp modeWhite smoke from exhaustBlack smoke when acceleratingRough or unstable idleCar keeps stalling

Frequently asked questions

What does code P0403 mean?

P0403: EGR control circuit. P0403 is a generic OBD code shared by all manufacturers since 2001 for petrol and 2004 for diesel. It relates to: emissions control. The code tells you what the ECU measured as abnormal, not necessarily which part to replace.

Can I drive with code P0403?

Monitor. You can drive normally but get it checked in the coming weeks. It may fail an MOT or roadworthiness test.

How much does it cost to fix P0403?

EGR valve: £275 – £740.

How to read this code

An OBD scanner plugged into the 16-pin socket under the steering wheel reads and clears codes. Bluetooth models cost £20 to £40. Clearing a code without fixing the fault is pointless: it comes back.