p0401
Moderate
Peugeot · SUVs
Exhaust Gas Recirculation (EGR) Flow Insufficient
Quick Answer
Error code P0401 on your Peugeot SUVs means: Exhaust Gas Recirculation (EGR) Flow Insufficient. This is usually fixable — see the step-by-step guide below.
Affected Models
Likely Causes
How to Fix It
1
Inspect EGR valve for carbon deposits
2
Clean EGR passages and valve
3
Test EGR position sensor output
4
Check vacuum lines to EGR valve
5
Verify valve opens at specified load
Pro Tip
This fix requires some technical knowledge. If you're unsure about any step, consider contacting support or a qualified technician.
Parts You May Need
EGR valve
EGR cooler
EGR position sensor
Gasket sealant
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