P0401
Exhaust Gas Recirculation Flow Insufficient Detected
Generic code
Auxiliary Emissions Control
Medium severity
Moderate repair
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What P0401 means
- The fault code P0401 indicates that there is an issue with the Exhaust Gas Recirculation (EGR) system. Specifically, the EGR flow is insufficient, which can cause a variety of engine problems.
Possible symptoms
- Illuminated check engine light
- Poor acceleration or reduced engine power
- Rough idle or stalling
- Increased emissions output
Possible causes
- Failed EGR valve
- Clogged EGR passages
- Faulty EGR temperature sensor
- Wiring or connection issues in the EGR system
- Failed engine control module (ECM)
Related parts
- Exhaust Gas Recirculation (EGR) Sensor: Exhaust gas recirculation (EGR) is an emissions reduction technique used in petrol and diesel engines. Problems lead to harmful emissions out of limit
Possible solutions
- Replace the EGR valve
- Clean or replace clogged EGR passages
- Replace faulty EGR temperature sensor
- Check and repair any damaged wiring or connections in the EGR system
- Replace the engine control module (ECM) if necessary
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P0401 on OBD DashX
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