Joined: Wed May 2nd, 2018
Occupation: Elevator Design Worlds Tallest Buildings
Interests: Ranger Based Vehicles and OFFROAD
Reputation Points: 2045
|Dang that stinks! I hate codes that wont go away...
You said you replaced the DPFE, do you have your old one? Are these plastic or metal?
I hear you on the aftermarket EGR tube I have fought many a battle with those SOBS, but with pry bars, a vise, etc I can usually get them to thread. However you do not need a new EGR line if your factory one has no holes in it and you can clean it out
You do have the DPFE sample tubes routed properly? Large one on the large side, small on the other?
Having them backwards would cause a code. I have to ask.
You may need to do a manifold vacuum test, make sure your intake is making enough vacuum to open and close the valve. Do you have any vacuum leaks? PCV valve seated? Any torn rubber boots or split plastic lines? How is your idle?
I still suspect bad DPFE even though you replaced it, these things go out easily and I have seen my share of BAD ones
Any way to try and swap the DPFE with one from another engine? a known good one?
the P0401 code is insufficient flow detected...the DPFE is what does the "detecting" you have already confirmed you have good "flow"
Check the wiring coming into the DPFE, make sure the pins are good and clean and seated, the wires are in good shape, etc.
Last edited on Mon Jul 22nd, 2019 04:59 pm by 410customs
I build custom RBV, specializing in drivetrain conversions, wiring, suspension and complete custom trucks