P0408
Exhaust Gas Recirculation Sensor B Circuit High
Generic code
Auxiliary Emissions Control
Medium severity
Moderate repair
Free on OBD DashX
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What P0408 means
- The fault code P0408 indicates that there is an issue with the circuit that controls the EGR sensor B. This may cause the engine to run poorly or not start at all.
Possible symptoms
- Illuminated check engine light
- Engine runs poorly or not at all
- Reduced engine power or acceleration
- Rough idle or stalling
Possible causes
- Faulty EGR sensor "B"
- Corroded or damaged wires or connections in the circuit
- Failed engine control module (ECM)
- Malfunctioning EGR valve
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 sensor "B"
- Check and repair any damaged or corroded wires or connections in the circuit
- Replace the engine control module (ECM) if necessary
- Clean or replace the EGR valve if it is malfunctioning
Free on OBD DashX
P0408 on OBD DashX
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