Repeat DPFE Sensor Failure On 97 V8 Mountaineer

[Tennesseepowerstroke]

Anyone else experience repeat DPFE Sensor failure on 97 302's or other years.
I have replace at the following intervals. I will also list vendor the replacement was bought from or brand name.
miles on vehicle miles since replacement
6-24-02 71,980 71,980 original Motorcraft
8-11-04 104,280 32,300 Motorcraft
4-14-07 147,140 42,860 Autozone
11-10-07 157,071 9,981 Autozone
6-20-08 163,695 6,624 O'Reillys
3-05-09 175,721 12,026 O'Reillys
12-15-09 185,366 9,645 out again

Anyone have any ideas as to why there have been so many failures?

 

[emtzach]

honestly its just the nature of the beast. electronics and heat dont mix well, its an electronic measurement of hot exhaust gases, overheats and stops working jmo tho also notice wich one lasted the longest and then 2nd longest, see where im going with this

 

[Skandocious]

Subscribing. I replaced mine at about 95k miles and it's now gone out again at about 115k miles. I'd also like to know what the deal is.

 

[emtzach]

i think its a combination of lesser quality replacement part and increases under hood temperatures from older cats becoming slightly clogged, mufflers same deal, the engine itself getting some miles and increasing in temp. it all adds up to me.. il bet some one have real tech backup i cant do mutch from work

 

[Skandocious]

My cats were replaced with new units probably around 10k miles ago... So if anything this 2nd sensor should have lasted long than the first. And it was a Motorcraft part.

 

[emtzach]

My cats were replaced with new units probably around 10k miles ago... So if anything this 2nd sensor should have lasted long than the first. And it was a Motorcraft part.

true but his original quote he used a motorcraft part as well and basically same results as you and its getting shorter intervals over time. but hopefully theres another answere for you guys i was just going with what made sence to me

 

[Tennesseepowerstroke]

The Motorcraft parts lasted the longest [with the exception of 1 Autozone part] but I fellt it was because the motor was newer with a lot less miles. It seems to be happening way too frequently now. I bought the DPFE at O'Reilly's for the lifetime warranty but changing it out so often is getting long in the tooth.

The motor seems to have as much power as it ever did. It has never gotten hot, by the gauge, and had the radiator replaced around 150,000 milels due to a miniscule leak that was hard to find.

The oil has always been changed at 5000 or less intervals. It has had Motocraft oil and filters except for a time from 95,000 to 165,000 miles I used Mobil 1 synthetic. I changed from the Mobil 1 back to Motorcraft because of the expense of having to add approximately 2 quart between changes. The engine does not leak a drop of oil and does not smoke. I assume this oil is leaking past the valve seals. Could this be causing this problem?

 

[O'Rattlecan]

DPFE?

Fill me in here folks.

Ryan

 

[Bricks]

DPFE = Differential Pressure Feedback - EGR

Simply put, it monitors EGR flow

 

[O'Rattlecan]

GOTCHA! Now I get it. Thanks.

Ryan

 

[nobodyspecial]

Does it throw a code when that sensor goes out? I have 130,000 miles on my 2000 Mounty 302 and nothing so far...

 

[Bricks]

A p0401 could point to it. (Insufficient EGR flow)

 

[Skandocious]

There is an actual DPFE code on OBD-I vehicles, so I'm sure there's one for OBD-II also. My OBD-I code that I'm getting is:

335 - PFE or DPFE sensor voltage out of Self-Test range.

 

[Tennesseepowerstroke]

Does it throw a code when that sensor goes out? I have 130,000 miles on my 2000 Mounty 302 and nothing so far...

It threw the P401 code this time as well as previous times. Sometimes it has thrown the P402 code [too much air flow] as well.

 

[emtzach]

The Motorcraft parts lasted the longest [with the exception of 1 Autozone part] but I fellt it was because the motor was newer with a lot less miles. It seems to be happening way too frequently now. I bought the DPFE at O'Reilly's for the lifetime warranty but changing it out so often is getting long in the tooth.

The motor seems to have as much power as it ever did. It has never gotten hot, by the gauge, and had the radiator replaced around 150,000 milels due to a miniscule leak that was hard to find.

The oil has always been changed at 5000 or less intervals. It has had Motocraft oil and filters except for a time from 95,000 to 165,000 miles I used Mobil 1 synthetic. I changed from the Mobil 1 back to Motorcraft because of the expense of having to add approximately 2 quart between changes. The engine does not leak a drop of oil and does not smoke. I assume this oil is leaking past the valve seals. Could this be causing this problem?

see now that makes sense too. if your getting blow by into the exhaust your getting a small amount of oil into that sensor that could be the cause. at leasat this makes sense to me

 

[Tennesseepowerstroke]

There usually is what appears to be white moisture stains on the plugs and hoses. I guess it could be blow by though.

Thanks for your responses. I was hoping one of the techs had seen this before and would offer some advice. Anyone know if they frequent the engine threads for gas engines. Seems to be a lot of help for diesels.