EGR recirculates exhaust gas back into the intake to lower combustion temperatures and reduce NOx emissions.

Can I just remove the EGR?

Removing EGR is illegal for road vehicles and will fail emissions. It can also cause engine knock due to higher combustion temps.

P0400

Medium Severity

Emissions System

The EGR system flow is not within expected parameters.

Common Fix

Clean or replace EGR valve

Estimated Cost (DIY)

$20 - $150

Carbon-clogged EGR valvelikely

Stuck EGR valvepossible

EGR passage blockedpossible

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What does EGR do?: EGR recirculates exhaust gas back into the intake to lower combustion temperatures and reduce NOx emissions.
Can I just remove the EGR?: Removing EGR is illegal for road vehicles and will fail emissions. It can also cause engine knock due to higher combustion temps.

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