I have read a lot of post on here about this but I am not getting anywhere. I have a 2000 ford f 150 4x4. I just had to replace the engine in it because something got in my engine and beat it up and bent a valve. I replace the engine with one out of a 99 f 150. By the way it's a 5.4 triton. The engine I installed was suppose to have around 77,000 miles on it. I noticed when I got it that the dpfe sensor was melted off of it and so was the hose on one side. I never had that problem with the original engine. I took the dpfe sensor off the destroyed engine and put it on the used one I installed. Low and behold in less that one day it melted off that one. I have read on here about cats being clogged and or the egr tube. I had no problem with my original engine so it's hard for me to believe the cats or clogged. I did happen to find a metal dpfe sensor off another truck and have installed. I am getting a rough idle now and not sure whats going on. I tried cleaning the egr tube the best I could without taking it off. Also the egr ports on the throttle body are cleaned and open and the egr valve itself is a new one. Any possible solutions from anyone?

 

A little background on EGR hardware and operation.
The metal pipe that connects between the exhaust manifold and the EGR has a calibrated restriction hole inside the tube .
The DPFE hoses connect accross this restriction as a means of measuring pressure drop and limiting max flow in that system.
If the restriction is missing, excess exhaust could heat the DPFE.
This should set a code as a 4xx or 14xx.
This operation is totally a diagnostic system on the total EGR operation
If the EGR is leaking either by fault or the vacuum regulator is sticking open the same thing can happen as excess flow.
The vac regulator has a filter inside the round cap that filters air on the closing of the valve. It may be plugged allowing the EGR to keep flowing when it should be closed off.
An EGR system leak will cause rough running.
If there is a fault such as this, a code should be set soon after replacing the DPFE and into a drive cycle because the computer tests this system 2 times before setting code for any fault detected.
A distroyed DPFE will also set a code because it can't measure and report to the computer, results from an attemped test.
A restricted exhaust could add to the issue.
Pay attention to the code set as a clue to what may be happening with attention paid to how it could overheat.
Good luck.

 

I have not had any more trouble out of it since i replaced it with the metal dpfe sensor.

 

Melted plastic DPFE sensors are usually cause by an exhaust restriction, usually clogged cats.

If you didn't transfer the exhaust system over, then you shouldn't have to worry about it.

 

Richard, plastic sensors normally do not melt.
Mine was replaced at about 35,000 but not from melting.
The original was plastic, the replacement is plastic and has been in service now for 162000 miles.
There is a reason yours melted.
Good luck.

 

You haven't mentioned if you have error codes or not.

 

The only codes that were sent were the ones showing a blocked or removed hose from dpfe sensor or something like that. I thought I have it all fixed and yesterday it melted the new hoses off. I got new hoses installed on it and now it keeps blowing off the bigger of the two. I don't know what to do with it anymore other than possibly changing that cats. If anyone else has anything or any other options please let me know something.

 

Back pressure test the cats . That will show the bad cat , or cats . A good shop can help . Good luck !

 

In the metal tube leading from the driver side exhaust manifold to the EGR valve is a .040" restriction.
This restriction is used by the DPFE to measure pressure drop across for the system testing.
If that restriction is enlarged or missing, excessive exhaust gas, pressure and attendant heat will affect the hoses and the DPFE that are not intended to handle that much heat or pressure on the hose connections.
To test for a possibility of this use a vacuum gage that will read a few lbs. of positive pressure on both sample lines.
Block the line not being tested each time.
If you see the same pressure both sides, the internal orfice is missing or damaged.
The 040 size is less than your spark plug gapping at about .053.
Plainly, if they are burnt or blown off there is excessive pressure.
The faster you go, the longer you run, the worse it gets under the conditions.
Please use common sense.
Good luck.