PO401, PO402 ... and ... P1401 codes?

[Don P.]

Thanks to all the tips and search features here, I found a scanner I could afford to run a diagnostic on my CEL

(BTW, I have a '96 XLT 4 x 2 and the 4.0 engine with about 135,000 miles so far. I plan to keep it on the road for a lot longer, with any luck.)

I was kind of surprised when I ran the codes though. It told me I have "EGR flow insufficient" and "EGR flow excessive" at the same time and "Mfr Control: Auxiliiary Emission Control" problems, all at the same time. It seemed strange to have both excessive and insufficient in the same diagnostic?

I reset the CEL but it came back on this morning so it's not a false reading obviously.

Any suggestions on where an old "points and condensor" back yard mechanic should start?

Thanks for any help you can offer.

Don P.

 

[Robb]

This will help you out a little: http://www.explorerforum.com/forums/showthread.php?t=110813

 

[Don P.]

Thanks for the tip. One question

I checked it out under the hood last night and I think I have the DPFE unit identified. But with so many lines running around there I wanted to check to be sure I have the right component before I start replacing expensive stuff.

(The Haynes manual wasn't very helpful in picking out the unit from diagrams or those tiny little line drawings.)

I found a rectangular component about 2 inches by 4 inches on the drivers side valve cover. It is held on with two small bolts. Pretty easy to get to.

It has two short (maybe 6 to 8 inches long at most) rubber (vacuum?) side by side hoses leading from the bottom to a metal tube that runs horizontally. One tube comes off the end of the metal line, the other about 5 inches in from the end. The unit has an electrical plug from the loom at the rear of the unit facing to the fender side.

Sorry to sound so dim about all this. But my "other" car is a '62 Triumph TR-3 and emissions hadn't been discovered when it was built ... or seatbelts or roll bars or much of anything esle.

 

['96explorereddiebauer]

Maybe this will help.

Source: Serious Explorations Forum

See right below the IAC (the metal cylinder shaped part), that plastic part is your DPFE. Yours may be in a metal case or not but since Ford has redesigned the part, it's plastic like the one shown above.

 

[B1942]

P0402

Don,
I lived with a P0402 code, supposedly bad converter for 3 years. Went through 2 smog tests with flying colors (after turning off the code with my reader) Needless to say I got tired of seeing that light all the time. If you go to WWW.Brickauto.com they sell an 02 fooler that wires into your existing sensor and eliminates the light. Still passed smog with flying colors.
B1942

Thanks to all the tips and search features here, I found a scanner I could afford to run a diagnostic on my CEL

(BTW, I have a '96 XLT 4 x 2 and the 4.0 engine with about 135,000 miles so far. I plan to keep it on the road for a lot longer, with any luck.)

I was kind of surprised when I ran the codes though. It told me I have "EGR flow insufficient" and "EGR flow excessive" at the same time and "Mfr Control: Auxiliiary Emission Control" problems, all at the same time. It seemed strange to have both excessive and insufficient in the same diagnostic?

I reset the CEL but it came back on this morning so it's not a false reading obviously.

Any suggestions on where an old "points and condensor" back yard mechanic should start?

Thanks for any help you can offer.

Don P.

 

[Styx]

Don check for dammaged hoses to the DPFE first. if they leak it will set codes. also the mettle tube that you are talking about is the EGR tube check it for leaks. The DPFE checkes how well the EGR is working by sampling the amount of flow across an orfice in the mettle tube between the two hoses. I have run across alot of the rubber tubes dammaged and a few DPFE sensors not working and one or two dammaged EGR tubes.
Also check to see if you EGR is working properly by applying vacume to it @ idle. The engine should run rough.

btw... I'm in the middle of a ground up on my 67 spitfire. just love the english rust...lol...

 

[Ray z]

Don,
I lived with a P0402 code, supposedly bad converter for 3 years. Went through 2 smog tests with flying colors (after turning off the code with my reader) Needless to say I got tired of seeing that light all the time. If you go to WWW.Brickauto.com they sell an 02 fooler that wires into your existing sensor and eliminates the light. Still passed smog with flying colors.
B1942

Bill I know this an ancient post, but was your smog test the tailpipe kind or they hooked computer up to your OBDII port.

Ray