p0401
Moderate
Lincoln · Sedans
EGR Flow Insufficient
Quick Answer
Error code P0401 on your Lincoln Sedans means: EGR Flow Insufficient. This is usually fixable — see the step-by-step guide below.
Affected Models
Likely Causes
How to Fix It
1
Check EGR valve for carbon deposits
2
Test EGR sensor electrical signal
3
Verify vacuum lines to EGR valve
4
Clean or replace EGR valve
5
Clear carbon from EGR passages
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 gasket kit
EGR sensor
Carburetor cleaner
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