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Discussion Starter #1
Alright guys, so simple job, right? Just remove the EGR, clean it, replace gaskets, and voila! Peice of cake! For the 3.8 guys! No, really. I noticed the EGR sits nicely behind the motor on our 4.6L, and is almost a PITA to reach. Anyone ever dealt with this? Oh, and not removing the engine would be nice. If there are any other solutions to this problem please let me know. Will I just be able to remove the heater hoses and get at it that way? Oh the humanity! Thanks!
 

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If you replace the DPFE sensor, you may as well clean the EGR passages out too. If you remove the plastic shroud that covers the windshield wipers, it will give you some more room. Not much more, but it will help. Took me about 2 hours to remove/clean/reinstall mine, and I'm a no0b at it. It took some "contructive" words to get back there, but it can be done. If you want a write-up on it, I have my instructions here still. It may help.

Jay
 

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Discussion Starter #5
Absolutely, if you could help in any way, send a link or what have ya. At least I can have an idea what I'm up against before I tear into it.

Thanks!
 

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Samurai said:
...Will I just be able to remove the heater hoses and get at it that way?...
If you can remove them, that'll help a ton. If they've never been removed before, the hoses may have "become one with the heater core tubes."

FordMan77's suggestion to remove the wiper cowl stuff is a good one. It's what I've done. I also undid the thick wiring harness that runs across there - if you go that route, be careful as you snake the harness through the A/C lines.

If you choose to tackle the DPFE sensor, I found it easier to remove the bracket it sits on (see #6 in the following drawing), then transplanting the sensor:




The most important item is patience, based on experience and what I read in other DPFE/EGR-related threads.

Here's the 1994 Service Manual How-To, if needed (1995 similar):



 

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When you go to bolt the elbow back on, make sure you get the surface of the intake clean so you get a good seal. That's a bad place to cause a vac. leak.

Also, when you go to put the 4 bolts that hold the elbow back onto the intake, stick a little gasket sealer in the socket you are using, so that when you are over the top trying to line the bolts back up and get them in, the bolt doesn't end up dropping into the intake, or back behind the motor somewhere.

bolt+piston= bad

Jay
 

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You can have autozone test the DPFE sensor while its out. Also when your cleaning out the passages you should put a rag into the hole to keep crap out of there.
 

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I would just take the TB elbow off and scrape/vacuum all the carbon out of the EGR passage. Here is the link http://www.lincolnsonline.com/article15.html

Dont take the EGR valve itself, the EGR tube or any of that off, too much work for no reason! Doing the other stuff is enough work, will take all afternoon. Scraping the passage out took me a couple hours alone - I then kept soaking the slot that goes to the EGR with carb cleaner and sucking up the junk with a bunch of Q-Tips.

Also, get new TB gaskets.

Al
 

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I would take the 94/95 intake off and melt it into beer cans.
I installed a 96 up intake on mine :).
Much easier to work with everything isn't crammed in the back of the engine.
Alan
 

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Discussion Starter #12
Okay, so I cleaned the upper plenum like T6rocket suggested. Man, it was dirty in there. Got everything assembled and... I still have the same problem. Slightly rough idle like an out of rhythm sub, and that dang check engine light. And I developed a nice whistle from what I guess is a vaccuum leak. Oh well, soon I will check and clean the EGR itself and see if that helps.
 

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Sorry it didnt fix it. It worked for me, but I didnt have any erratic idle, just a CE light for 2 years!

Did you check the red & green plastic EGR vacuum lines? Could have a crack. They are brittle, I broke mine taking it off. Pieced it together with a piece of hose since you cant get them new.

I would pull them off and check.

Al
 

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Discussion Starter #15
Hmmm, I wouldn't describe it as erratic. I mean it's a slight misfire almost. Like I'm idling at a red light and I can feel it thump in my seat. I thought that may be a bad motor mount too.

Al, I must say I'm glad I cleaned that spot out though. Throttle response it better, and I got like a 20 hp jump! LOL I thought for sure after seeing how bad the carbon was in the passages that it would cure the prob too. Not to worry though, I'm just right back where I started. I'll have to check the red and green lines when I pull the EGR. I'll keep you guys posted.
 

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What is the DPFE sensor? My gf's Explorer threw an EGR code, so I'm trying to figure out what would do that, other than an actual bad EGR valve.

Thanks

Sean
 

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reitman said:
What is the DPFE sensor? My gf's Explorer threw an EGR code, so I'm trying to figure out what would do that, other than an actual bad EGR valve.

Thanks

Sean
It's the rectangular,aluminum box with a connector on it and 2 hoses running to it from the egr tube.
Alan
 

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Step dad (professional mech) took off all the intake plastic and put a towel over the manifold and leaned over towards the back, he weighs like 300 lbs too, its a wonder he didnt crack that manifold!

- Pelezo
 

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reitman said:
What is the DPFE sensor? My gf's Explorer threw an EGR code, so I'm trying to figure out what would do that, other than an actual bad EGR valve.

Thanks

Sean
The technical definition, from the 1994 PC/ED manual:

DPFE Sensor
The DPFE Sensor is a ceramic capacitive type pressure transducer that monitors the differential pressure across a metering orifice located in the orifice tube assembly. The DPFE Sensor receives this signal through two hoses referred to as the downstream pressure hose (REF SIGNAL) and upstream pressure hose (HI SIGNAL). The HI and REF Signals are marked on the DPFE Sensor housing for identification (note that the HI Signal uses a larger diameter hose). The DPFE Sensor outputs a voltage proportional to the pressure drop across the metering orifice and supplies it to the PCM as EGR flow rate feedback.



My 2¢:

From what I've observed, the DPFE sensor has been a very common issue in warranty and out-of-warranty EGR-related problems. The EGR valve rarely goes bad - it's the DPFE sensor that's faulty.
 

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Thanks, that helps a bunch. Is this a part I'll have to get at the dealership, and how much am I looking at?
Also, what does DPFE stand for?

Sean
 
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