Powertrain
generic / SAE
P0402
Exhaust Gas Recirculation Flow Excessive Detected
EGR flow is higher than expected when the valve should be closed, or higher than commanded when partially open. Typically a valve that has stuck open due to carbon, causing rough idle and stalling.
SystemPowertrain
Typegeneric / SAE
GroupP0
Range / number4 / 02
Possible causes
- EGR valve stuck open high
- Valve seat eroded — does not seal medium
Inspection / repair
- Difficulty: medium
- DIY: possible
- Estimated cost: 60–700 €
- Estimated time: 1–5 h
- Component: egr valve
- MIL / check engine light
- emissions-relevant
- drive cycle required
Sources
References
sae:J2012