Bad DPFE?

[Lazzman]

I have recently experienced the same problems that I did a year and a half ago when my DPFE sensor went bad, heavy surging while driving, very poor idle, very bad smell of exhaust from the engine.

The engine finaly threw a code and I am going to get it checked out today at Autozone.

Question is: If it is the DPFE again this would be the 2nd one I have replaced in two years. The first one was a Napa model that failedafter a year and the current one is a genuine Motorcraft part. I have put less than 15k mi on the vehicle since I replaced the DPFE, vacuum motor, EGR valve and EGR tube.

What would keep causing the DPFE sensor to fail?? Also what is the purpose of the DPFE sensor and is there anyway to test it? I read that I could disconnect the vacuum hoses going to the EGR tube and plug them and that would bypass the DPFE sensor, is this true?

Any help is greatly appreciated.

 

[EMG7895]

is it a metal one or a plastic one that failed?

 

[Lazzman]

Its a plastic one made by Motorcraft.

 

[2000StreetRod]

DPFE sensor failure

I've read that many DPFE sensors are not really failed but clogged due to constant exposure to condensation. Do you still have the heat sleeving on the EGR tube? It helps the tube retain heat and reduces condensation.

EGR increases the life of your exhaust valves by reducing the combustion chamber temperatures. Before EGR, exhaust valves would only last about 75,000 miles even when the fuel mixture was rich to reduce combustion chamber temperatures. Now engines with over 200,000 miles still have decent compression.

For more info click on the EGR related link in My Helpful Threads.

 

[Lazzman]

Thanks for the info.

Took it to Autozone today and it came up with code PO402. This pretty much points to a failed EGR pressure sensor.

Question is why am I going through so many of these parts in such a short amount of time??

My engine is older and has 200k mi on it but it does not use a lot of oil and runs great. Don't imagine there could be that much blow buy but who knows for sure.

 

[toypaseo]

What kind of hoses are you using on the DPFE? They should be silicone based, according to my ex-Ford mechanic neighbor who just changed mine to that type.

 

[Lazzman]

Yes, they are silicone hoses a direct replacement from Motorcraft which I picked up at the Ford dealer.

Funny thing happened when I replaced the Pressure Feedback sensor today, after I took it out and moved it around a bit water came out of both plastic fittings. Not an expert but it does seem kind of odd to me, maybe the vapor canister is not working properly anymore. Either way it does not seem right that an electronic component that regulates exhaust flow should have water in it.

Before anyone asks, yes I am sure it was water and not another engine fluid, and it was clear & clean.

Any suggestions??

 

[Lazzman]

No one knows why I would have water in my DPFE sensor??

 

[kdbstl]

I'm having the same problem with that sensor. Does the high voltage code mean it has failed? I bought one from carquest in April and its throwing the code. I'm going to check it soon to see about water. Hopefully we can find some solution.

 

[gtyates]

The last time I replaced mine it also had water in it and unit was barely a year old. I really can't answer the why, but just saying I experienced the same thing on my '97 truck with OHV motor with lower mileage than yours (it had about 120k at the time). I did find though that buying the parts store brand was not a good idea as it barely lasted a year before having the same issue. Replacement I bought was a Motorcraft and was still doing fine when I sold the truck with about 135k on it. My current '96 model still has the oem DPFE in it with 113k miles on the truck. I do not know if there is a connection or not but right after the parts store brand failed I got the lean on bank 1 and 2 code indicating the upper intake gaskets needed replacing. Maybe those gaskets failing were letting in enough air/moisture to cause the problem?? On my '96 I replaced the upper intake gaskets as part of the the process of replacing the camshaft position sensor so the gaskets never got that bad in my '96. But water is a by-product of combustion.

 

[watergate528]

Misinformation

I've read that many DPFE sensors are not really failed but clogged due to constant exposure to condensation. Do you still have the heat sleeving on the EGR tube? It helps the tube retain heat and reduces condensation.

EGR increases the life of your exhaust valves by reducing the combustion chamber temperatures. Before EGR, exhaust valves would only last about 75,000 miles even when the fuel mixture was rich to reduce combustion chamber temperatures. Now engines with over 200,000 miles still have decent compression.

For more info click on the EGR related link in My Helpful Threads.

What are you smoking down there in SC??

Majority of DPFE's fail because they are made cheaply.
EGR increases the life of your exhaust valves? Really?
The temperature reduction in the combustion chamber of an egr engine versus a non-egr engine is minimal. Nowhere near enough to extend exhaust valve life.

Engines run 200K & beyond because the LEAD was removed from the fuel & the AF/Ratio is controlled through a computer.

Most engines that croaked because of burnt exhaust valves did so because of exhaust restriction.
The old 289-302's were notorious for burnt valves.

You are just a wealth of misinformation! :thumbdwn:

 

[BubbaFL]

 

[BubbaFL]

I have no idea what would cause your DPFE to die so quickly.

For what it's worth, I have 160k on my stock one, it's literally held together with duct tape, dollar store epoxy, and some tubing from my broken camshaft oiler, and it still works fine even after 14 years in the Florida heat and humidity.

 

[2000StreetRod]

EGR extends exhaust valve life

According to Cambustion Limited EGR extends exhaust valve life: EGR and NOx Measurement

 

[2000StreetRod]

DPFE failure?

What are you smoking down there in SC??

Majority of DPFE's fail because they are made cheaply.
. . .

In response to the post about DPFE sensor.
Being I work for the company that designed and manufactured the sensor for Ford Motor Corporation I cannot mention the company name. I think I need to add a few statements and clarify some problems here. I am a design and failure analysis engineer for this project that is no longer in production. As stated it is a differential pressure transducer that is designed to read the difference of pressure across the EGR valve opening. You have stated that “heat was the cause of the electrics failures” well that is not true the internal sensor and the electronic are made of ceramic and high temperature solder designed to work at temperature above 150C. The 1500C exhaust stream does not pass through this transducer the pressure applied to the sensor is a dead head so the thermal transfer is contained to the stagnant air trapped in the hoses to the sensor that is very slow to transfer heat. The real cause of the failures is water and trapper acids in the water. Ford did a poor job of preventing the build up of water in the EGR system which ended up corroding the inner seal glades of the transducer and allowing the water and acid to come in contact with the electronics as you a know water and electricity do not mix. The biggest cause of the failure was do to short trip driving which did not allow the water to be removed from the system and a build up would happen at a higher rate. . . .

Now the second transducer plastic was a second source for these transducer and they had a higher failure rate then the Aluminum housed transducer. The plastic housing was to reduce cost of this transducer not to dissipate heat in fact the plastic transducer would melt with pressure leaks.

The sensor has had a very good track record over the years there were over 4 million sensors produced a year for 5 years and the return rate was 10 parts per million which is pretty dam good being these transducer have to last at least 100000 miles without failure in a very nasty environment.

 

[jevchance]

That just happened.

 

[WerxRacing]

well now i had people say to get plastic over the metal. i have put 3 on my 98 2.5 ranger in the past 10mnths. even did one a mnth ago. no codes yet. runs better but still jerkn. after all this time no one on any forum has a good answer on how to fix this. i decided to to bypass. so hit google for a search & found this thread. i have replaced egr valve & sensor, both o2's, dpfe 3 times now. even this last time i got codes for dpfe & iac. so did them. this dpfe is driving me nuts.

 

[azvampyre]

I have to agree with watergate. This post is a wealth of misinformation.
Plus, Ill add that your iac isn't throwing a cel code because it isn't read by the PCM, and wildbil jibberjabbing about the track record of the dpfe which has the highest failure rate of any oem part to date. 87% fail within 4-7 years, or 45,000 miles. Why do you think it is one of the highest selling auto parts on eBay, with just under 97,000 sold in the past 10 years?
I see now that this entire site is a joke cluttered by drunks and psychopaths.
We are now all dumber for having visited this crock of 6th grade graduates.

 

[Bobmbx]

[deleted]

Oops, wrong thread.

 

[2000StreetRod]

IAC valve DTCs

. . . Ill add that your iac isn't throwing a cel code because it isn't read by the PCM . . .

You are correct that the PCM does not read the IAC valve - it has no electrical output. Instead, the PCM commands the IAC valve to a desired value and then measures the engine speed via the crankshaft position sensor. The PCM creates and stores a delta for the commanded vs actual engine speed and applies that to future commands. When the PCM is unable to achieve the desired engine speed via the IAC valve it sets a DTC. Examples are:

P0505 Idle Control System Malfunction
P0506 Idle Control System RPM Lower Than Expected
P0507 Idle Control System RPM Higher Than Expected