EGR mystery

[Andrew1941]

jdpk,

The bucking on mine has been eliminated about 99% from fixing the minor vaccuum leak I had at the EGR valve connection. I say there is 1% left because I have had one or two minor incidents since I fixed the leak, but otherwise it is now gone. I still have the P0401 code up, but the van is running completely fine. I have not found the reason yet for P0401, but I haven't had time to look either. I suggest you check all those vacuum connections very closely. If anything is loose, then do what you can to tighten it. My problem was the rubber elbow on the EGR valve would spin freely and easily slide of the valve connector. It would stay on without coming off on it's own, but just being loose enough to turn was all it took. I only knew that it was supposed to be tight because when I grabbed the elbow on my sister's van, it was tight at first, but then it became loose after I removed it once for inspection so we replace the elbow and now it is difficult to remove let alone turn. Mine was loose to begin with so I knew I had to do something. Check that vacuum line really closely from one end to the other for any kind of a leak. You can remove all the components and blow into them with one end sealed to check for cracks and if anything is loose, try tying a zap strap around it or temporarly tape it to see if it helps.

[Andrew1941]

Found some good stuff on EGR valve, DPFE and testing. A bit vague, but it really helps when you better understand how it all works when you are troubleshooting.

http://autorepair.about.com/library/faqs/bl656h.htm

http://car.justanswer.com/car/1i9x-2001-windstar

These last three are fantastic explanations and troubleshooting information. If you want to learn about EGR systems, then read these links...

http://en.wikipedia.org/wiki/Egr

http://www.asashop.org/autoinc/nov97/gas.htm

http://www.asashop.org/autoinc/dec97/egr.htm

[Andrew1941]

Last night I cleaned the vent on the solenoid, which really wasn't plugged and I tested the EGR valve (proved it works) and tested the DPFE sensor and proved that it didn't work. Replaced it and reset the CEL. Seems better, but I hate to say I fixed it until a while has passed. I will report back. Then I may post some pictures and details on what I did...

[jdpk]

Case closed. Number 3 plug fouled badly. Changed the whole set and wires and she runs (almost) like new. 147K and still chugging. Think the DPFE (motorcraft) and vacuum solenoid fixed the codes.