AssumedDoc
Active member
So last week the check engine light came on so I scanned it and came up with the P0401 code. Read up on it and wasnt to worried. Then I was washing my car on Friday night and noticed soot on the tips, which was never there before the code. Went on a 300 mile trip yesterday and only averaged 30 mpg's running 75(averaged 35-36 before). Is it a good guess the dpf is shot? Egr also shot too? On a 2010 jsw tdi.