P0404 fault code: what it means

P0404: EGR valve position does not match what the engine computer commanded.

Engine and gearbox (powertrain) · Minor

Usual causes, most likely first

carbon build-up restricting the EGR valve
faulty EGR position sensor
worn or sticking valve mechanism

P0404 by make

GWM

EGR circuit range/performance: valve not where commanded.

Usual causes: carbon-fouled or sticking EGR valve; EGR position sensor; EGR wiring

Isuzu

EGR circuit range/performance: valve not where commanded. Can bring limp mode.

Usual causes: sticking or carbon-fouled EGR valve; EGR position sensor; EGR valve wiring

Jeep

EGR circuit range/performance (CRD diesel).

Usual causes: sticking EGR valve; EGR position sensor; wiring

Kia

EGR range/performance on 2.2 CRDi Sorento-type diesels; can cause limp mode and rough cold idle.

Usual causes: faulty EGR valve (some aftermarket valves don't suit these engines); EGR wiring or connector fault; carbon build-up in the valve or intake

LDV

EGR circuit range/performance.

Usual causes: sticking or carbon-fouled EGR valve; EGR position sensor; EGR wiring

Mitsubishi

EGR valve range/performance: the valve is not reaching the position it was told to.

Usual causes: carbon build-up on the EGR valve; sticking or worn EGR valve; EGR position sensor fault

Volvo

EGR circuit range/performance: valve not where the ECU commanded.

Usual causes: sticking EGR valve; EGR position sensor; carbon build-up

What the repair usually costs

Parking sensor replace, one sensorNZ$130–NZ$520 · A$130–A$510
Intake valve carbon clean (walnut blast, direct injection)NZ$530–NZ$1,190 · A$560–A$1,240
EGR valve replacement or cleanNZ$350–NZ$1,710 · A$330–A$1,630

Not sure what P0404 means on your car? Ask Credov.

Before you clear it

Write the code down or photograph the scanner first. A code that comes straight back after clearing points to a fault that is still there. A car whose codes were cleared just before you arrived may be hiding one: the scanner's readiness monitors show "not ready" for a while after codes are cleared.

Researched by Credov from manufacturer and workshop sources. A fault code points to where a fault may be; a workshop confirms it with a diagnosis. Browse all fault codes.