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P401 code

07-09-2011, 09:17 PM
My daughters 98 Escort wagon has been throwing a P401 code for some time now. After reading several other forums I found the DPFE sensor is the culprit 95% of the time, or so they say. Replaced it and after about 30 minutes of driving it came back on, the same code. So anyone with any helpful advice out there?

I plan to remove and clean the EGR valve tomorrow as well as clean any other restricted passages. Am I going to have any problems getting the EGR with its long tube attached out of there. I looks like it may be a bit difficult. Thanks for any help.

07-10-2011, 02:45 PM
95% of the time it's the DPFE sensor. If it sounds to good to be true it probably is. Looks like I wasted money on it. I removed the EGR and its associated tube, which was quite easy. One of the steel tubes branching off of the main tube was completely clogged. Got that one cleaned. And I ran carb cleaner through the main tube back and forth until it ran mostly clear. I was about to reassemble everything when I thought to look at the hole in the intake manifold where the EGR mounts to. Had to use a bright flashlight and a mirror. It was completely clogged with carbon. I ended up breaking several pea sized chunks out of it. Put it all back together and so far so good. Oh and if the parts store only has the EGR mounting gasket it will work for both the EGR and the tube. The hole sizes and spreads are the same it's just the outside dimensions that are bigger on the ERG one.

07-11-2011, 03:43 PM
Much thanks for providing the feedback on the fix. Its easy to forget that EGR tubes are probably half clogged on any Escort, and many other cars that have a longish tube from exhaust to intake.

I have had to clean out a few such tubes; on my mopar vehicles; I should probably check the tubes on my three 2nd gen. Escorts too.

07-20-2011, 09:52 PM
Update. 10 days later and still no check engine light and it's running great.

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