How to: Diagnosing DPFE Sensor (P0401 and P0402) with Scan Tool

[elliswife]

Mine also has two lines into it...so confused.

 

[cjp_xsport]

Sorry elliswife...I'm confused a bit now as well. Guess the Haynes manual is a bit misleading in this area for the older ex's.

The DPFE I replaced on my '02 was the same as the DPFE I replaced on my 2001 Ford Focus...both were plastic housings with connections to small diameter hoses. I remember when I was researching a CEL issue on my Focus that the guys on the Focus forum listed links to an older DPFE...I'll try to look for those links again to see if they might shed some light on this...I'm not expecting much out of this...

Again, sorry for wasting your time...

 

[cjp_xsport]

elliswife...have you checked with your local Ford dealer to see if they offer a wiring harness adapter for the updated DPFE sensor?

 

[elliswife]

No I haven't actually... I know the local "parts stores" don't list it.

 

[elliswife]

No time waste... it's a mission to figure out a lot of things on these rigs. Exploder=8th Wonder of the World. Even Ford mechanics admitt it (I used to work at a stealership as a receptionist).

 

[N182NS]

Diagnosing DPFE Sensor

I had a 96 Explorer and just bought an 02 last year, I had to replace it on both. My diagnosing is as follows: disconnect vaccum hose for egr valve with engine running apply vaccum to the egr valve, if the engine runs rough or tries to kill then the valve is working and their is no blockage and the egr valve is good. Replace sensor. thanks Nick

 

[Allcruisen]

Checking Voltage on my Plastic DPFE? On the left, I have the three prongs. From where to where am I supposed to check Voltage, using an Amprobe Volt meter?

Is the ign. switch to be on?

Also, Is there a way to convert from the one on the fire wall to the smaller one, via changing the plug? Which wire would go were?

Sorry for all the questions, its just I cant see myself paying $146.00 Dollars at the Stealership...

Thanx in advance,
Allcruisen

PS Great Write up

 

[l1tech]

I had a 96 Explorer and just bought an 02 last year, I had to replace it on both. My diagnosing is as follows: disconnect vaccum hose for egr valve with engine running apply vaccum to the egr valve, if the engine runs rough or tries to kill then the valve is working and their is no blockage and the egr valve is good. Replace sensor. thanks Nick

That works well for testing the actual egr valve but what about testing the solenoid that controls the vacum to the egr valve, what about testing for vacum to the solenoid and last but not least what about testing for the pcm's ability to control the vacum solenoid.

 

[andysride]

monitor dpfe reading on scan tool ,apply vacuum to the egr valve at idle engine should stumble indicating egr is working. check reading on scan tool if it doesn't change its the dpfe sensor. nice easy check .

 

[KPT]

All 1995 and earlier models and 1996 5.0L V8 models are equipped with the Pressure Feedback Exhaust Gas Recirculation (PFE) system.

The manual is incorrect here. My 95 has a DPFE. Stock was the metal casing. I replaced it with an autozone part and it failed again a year or two later. Got a genuine ford DPFE, it was the updated plastic part with a wiring harness, cut and soldier deal.... Hasn't failed yet.

1. Where is the DPFE sensor located on a 97 Explorer 5.0? Can't find it for the life of me! I have a bad feeling I have to pull the intake to get to it, though...

Its on the back of the intake manifold. Towards passenger side, right next to the EGR. Pain in the ASS to change, you have maybe an inch to work in.

Oh and OBDI will troubleshoot DPFE failures better than OBDII. My brother owns a 2000 5.0, I forget the exact codes but it was throwing a insufficient EGR flow. Took that DPFE off the 5.0, put it on my 4.0 (long after I had soldered on the new wiring harness). I drove maybe a mile and a half. MIL was not illuminated but I checked the codes anyway, had thrown a EGR pressure is/was out of range.

 

[High_Order1]

.....and, in the beginning of 2005, they started bolting the dpfe to the top of the egr. No more just buying the dpfe, you hafta buy the entire high-dollar assembly.


-Shawn

 

[Nebraska Ranger]

DPFE and P0401

I would like to thank those for posting all the good information on this thread,
Especially ExplorerDMB,and wildbill
I have just replaced my D.P.F.E. for the 2nd time in 19 months, i bought it from AutoZone in late October of 2006, fortunately it was under warranty (2 years) and I was given a replacement, I'am very interested in the water vapor and acid build up in the E.G.R. system, I run E-85 exclusively in my Ranger, and anytime somebody mentions water as being a issue, I listen!

So is there a way to prevent or drain/clean the system periodically to stop these expensive little sensors from failing? or am I barking at the moon?

Thank-You Again!!

 

[cmt08]

this thread has been very helpful. Thank you all. I have an 02 explorer and when I turned on the ac one day the service engine light came on, advanced auto scanned it and said it was an egr insufficient flow. everyone at advanced auto said clean out the valve, everyone here says to replace the sensor, and everyone at ford never heard of that even being a problem. LOL! I am not to engine smart so instead of the valve replacement it sounds like i should replace the sensor first. my only questions is if i unhook my battery for ten minutes is that good enough to reset the computer or do i have to delete the codes with a scanner? i did the battery thing once and the light went off for about twenty miles and then came back on.

 

[cmt08]

ok I bought a aftermarket sensor at advanced auto for thirty dollars and put it in today, it took a whole ten minutes. when i started the truck it seemed to idle better and the service engine light was off, but i contribute that to the unhooking the battery. well i will drive it for awhile and see what happens. i hope that was the problem and now it is fixed. if not then i will check the egr valve next.:bsnicker:

 

[joutlaw]

Does a 2005 VIN K Explorer have a DPFE?

A friend of mine is getting P0401 and P0402 on his 2005 VIN K.

I'm trying to find the part but not having much luck at NAPA, Autozone, Advance, or O'Reilly's.

 

[cmt08]

are you asking about the egr or the sensor. what part?

 

[cmt08]

It should. If you are getting the codes then you have an egr, then you also have to have a pressure sensor to go with it. mine is a 2002 xlt so I would think your friends would be no different. I do know all models in that year had a egr valve. Try asking for an egr pressure sensor, I know it is called a couple of different things. if all that fails then get a price check on an egr valve and see if the computer shows a sensor that comes with it. And I did fix it. it was only the sensor. I was kind of hesitant because the rig has 95xxx on it and I thought maybe the the egr was gummed up and had to be changed, but after I changed the sensor the light went off and never came back on. And I did not even reset the computer, the light went off on its own. So glad I found this site, I saved $400+. Again, the part was only $32 at advanced auto in Elk River MN, and it took 10 minutes to do. If you still cant find the part let me know and I will give you the part number off the box of the one I bought.

 

[joutlaw]

Thanks CMT... if you don't mind.. what were those part #s...

Here is what I posted in another thread...

I have a friend at work with a 2005 Explorer with the 4.0 VIN K motor with the check engine light on.

He is getting a p0401 and p0402 when the codes are read at Autozone. I've done some searching it comes back to the DPFE sensor, but I haven't found a part store that carries it for the 2005 model. I did some more searching and it's come back to the part is integrated into the EGR valve itself.

Should we replace the complete EGR assembly or am I just not able to find the part for the DPFE for the 2005?

Does anyone have the part #s for either the EGR valve assembly or the DPFE for the 2005 VIN K?

Is this an DIY fix that could be done with simple hand tools. We plan on doing the job after work one day this week if I can locate the part.

Thanks

 

[Cooldave52000]

I can't find the DPFE Sensor

I have 2002 Ranger XLT 4 Liter with 48,000 miles the error code is P1400
I have looked for the sensor but I can not find it.
Any clues or pictures would sure help
Thanks
Dave

 

[cmt08]

ok guys i will get the number off the box in the morning and post it some time on Thursday.