[xxxcellarator]

Hello, I just did a fuel filter change about 2 weeks ago. I don't see how this would have anything to do with it, but I saw it mentioned in a few topics while doing some research. Since about 2 days ago I noticed that the car was slightly jerking at lower speeds. And today the engine light came on. It gave one code: P0401. After reading through the forum, there seem to be too many possible causes to this problem. I need some help as to where to start. I have no clue where the EGR valve is located or where the PDFE sensor is. Any help would be greatly appreciated.

 

[drjkel]

P0401: Insufficient EGR Flow

Your first step is to replace your DPFE (Delta-Pressure Feedback EGR) sensor. On the duratec there are two possible types. One is often bolted on the drivers side of the rear cylinder head. It is usually necessary to remove the throttle body to access it. Two hoses lead from it to the metal tube that runs from the rear exhaust manifold to the EGR valve. The other DPFE sensor type is freestanding on top of the two hoses. Carefully match the plug on your car to the replacement part's socket. This sensor is a known pattern failure in many different Ford vehicles.

A new part is ~$75or ~$40 from Rock Auto depending upon type. It is usually recommended that you use the Ford part. Search this forum using the keyword "DPFE" and you will get numerous pictures and instructions. If this replacement doesn't fix you symptoms, then things get more complicated, but for your symptoms, this is usually the first step.

Good luck. Let the forum know how you make out. That's how we all learn.

 

[NKENN]

A common problem with these engines is that the EGR passage in the intake manifold gets clogged with carbon which blocks the EGR flow. Do not replace any components until you clean the EGR passages. Do a search on P0401 or EGR passage blocked. Good luck!

 

[xxxcellarator]

Ok, upon farther reading i realized that i should probably check the passages for carbon build up before i replace any sensors. The car does have 271 000 km, so i wouldnt be surprised if there was a carbon build up. Now, im not sure what exactly to clean. Here are a few questions i have:

1. Are these the two passages that i have to clean? The ones that the red arrows are pointing to? One going to the EGR valve from the exhaust and another going to the engine intake.

[attachment=28791:egrvalve.JPG]

2. Can i clean these by taking the EGR Valve off (ive seen some ppl say they cleaned it by taking the throttle body off, but it seems like too much work and unnecessary.)

3. And how do i take it off? Just undo the bolts at the top and the ones at the bottom?

4. Will i need 2 new gaskets? One to the engine intake and one to the valve exhaust intake?

5. And is there anywhere else i should clean? Any other tubes or passages?

Another thing i wanted to mention is that i did the test that i read about in the other topics, where u suck air from the valve to see if the engine dies down and comes back to normal and it does it just fine. Also, i tried sucking on it while the engine was stopped.
6. I sucked as much as i could and waited for 20 seconds, and the tried again and still couldnt suck anymore air, so this means that theres a perfect vacuum, no leaks anywhere, correct?

7. I cant find the DPFE sensor and i looked everywhere. behind the intake, behind the engine on the left and on the right and cant find anything like what people have been showing on this forum. I did however notice 2 metal pipes sticking from the exhaust tube that goes into the EGR Valve, which were connected to a sensor via rubber tubes. This sensor was very small however, about the size of a box of matches, and was only suspended in the air around the middle of the back of the engine. Is this the DPFE sensor on my car?

Thank you for all your help.

 

[drjkel]

If your engine stumbled and nearly died when you applied vacuum to the EGR valve, your EGR passages are fine.

"I did however notice 2 metal pipes sticking from the exhaust tube that goes into the EGR Valve, which were connected to a sensor via rubber tubes. This sensor was very small however, about the size of a box of matches, and was only suspended in the air around the middle of the back of the engine. Is this the DPFE sensor on my car?" YES. That is your DPFE sensor. That is also the more failure prone of the two varieties. The replacement, part is I believe, Motorcraft 4U7Z-9J460-AA, the less expensive of the two varieties.

There is an official Ford TSB (Technical Service Bulletin) on this very problem. I here provide a link to another forum where the TSB is published in its entirety:

http://www.ford-trucks.com/tsb/fulltext/sh...php?tsb=04-11-1

Note that while this TSB is in a Ford truck forum, the TSB applies to the model year 2000-early 2002 Taurii. You can join the truck forum for free and read the entire TSB but the relevant information is in the link.

Be very careful removing the two hoses from the sensor. They are made of a special silicone rubber to withstand the exhaust heat and are hard to find replacements for.

 

[02taurus]

I would just clean the passages and the egr valve it's self.I just had that code come up and I cleaned those out and code has not come back.same yourself some green by trying to clean them out with throttle body cleaner and see if code comes back.

 

[xxxcellarator]

Ok, heres an update. I just finished cleaning out the two passages. I removed the EGR valve and cleaned the intake into the engine and the exhaust hose that comes to the EGR valve. I did this by spraying into both of them a good amount of brake cleaner. I did not have throttle body cleaner so i used that instead. Also cleaned the EGR valve. One thing that was a little disappointing was that i couldnt see the end of the intake tube that goes into the engine. So i couldnt see if it was cleaned all the way through. But in any case, it didnt look too bad to begin with.
Put everything back, and reset the Check Engine Light. Went for about a 10km drive. Everything seemed to run perfectly fine and the light did not come back on. I will be driving more tomorrow, so i will be able to see if it truly fixed the problem or not.

P.S. Is throttle body cleaner much better than brake cleaner in this case? Should i have used that instead?

 

[OldWagon]

Cool that it helped, and I learned something from the thread.

As to the cleaning solvent, throttle body cleaners are available in "sensor safe" formulations, I think primarily to avoid fouling oxygen sensors. However, if the solvent you used evaporated before you started the engine, you'll have no problems. I work so slowly that evaporation would have taken care of any potential problem for me.

 

[xxxcellarator]

Ok, after a day of driving and 100km, the light did not come on anymore. The last time i reset it, it came back on in less than 10km of driving, so it looks like the cleaning worked . Thanks for all your help.

 

[xxxcellarator]

Today i had an unpleasant surprise. Just five minutes of driving after i got out of the garage, the CEL came back on.

On to plan B. So on my way home i dropped by Ford to get a replacement DPFE sensor. The guy gave me the following sensor with code 4U7Z-9J460-AA, and he said it'll do the same thing. I just wanted to check with you guys, is this the same sensor? Why is this one so different? The code for my sensor is 2FIE-9J460-AB. Here is a picture of both:

[attachment=28805SC04646.jpg]

[attachment=28806SC04648.jpg]

Another thing is, when i removed the sensor i noticed quite a bit of moisture inside of the tubes. There were droplets of water inside. I remember reading somewhere about moisture in the system being an indication of something. Does the moisture mean that there is something wrong somewhere?

 

[lotaparamoi]

I currently have the same CEL code right now. Is the sensor in the same location in a vulcan?

 

[xxxcellarator]

I believe it is, because i was in the junkyard just yesterday getting a few other things for my car when i saw a Gen IV taurus with a vulcan engine. It had a DPFE sensor located in the exact same position and it looked identical to the one i had, only it had a different code than mine (YF1E-9J460-AD). Took it anyways. Out of curiosity, does anyone know if this sensor would work on the Duratec? It looks identical.

 

[drjkel]

The 4U7Z-9J460-AA DPFE sensor is an *improved* part. That is why it looks significantly different. I am astonished you got as far as you you did with what appears to be the original DPFE sensor. Incidentally, the 2FIE-9J460-AB part is the exact part that failed in my 2000 'tec. I believe it to be unlikely that the Vulcan DPFE sensor will work for the Duratec. Perhaps someone else in the forum can comment, but for peace of mind, I'd go with the new part. The water in the tubes is a by-product of combustion and is to be expected.

Good luck. Let the forum know if this fixes the problem.

 

[xxxcellarator]

Thanks for that, definitely helped clarify a number of things. Its good to know that they improved the sensor. As for my car, the moment i put the new sensor in i felt a huge change. The car responds much faster when accelerating from a full stop, and might even be running smoother (could be just a mental effect). And it was jerking ever so slightly (probably due to misfiring) before which it isnt doing anymore.

So its certainly looking far more promising now. Once i get about 500km run with the new sensor and no CEL, ill repost to confirm that i did indeed fix my issue. Thanks for all you help.

 

[xxxcellarator]

Heres an image i took of the EGR sensor inside thought it would be interesting to look inside before i junked it. It is cracked because i opened it by hitting it with a hammer lol.
The liquidy looking thing is actually a very soft gel thats poured onto the entire sensor to protect it. Its very sticky too. Interestingly, the gel is also over the two contact points inside the circles where the exhausts enter. Wonder how they get the signal if the gel is blocking them.

[attachment=28827SC04649.jpg]

 

[xxxcellarator]

Just a quick update. After more than 500kms of driving back and forth to University, the EGR has not come on anymore. So changing the sensor fixed my problem . I was sure it did the moment i felt the car run with the new one. Thanks for all your help once again.

 

[drjkel]

Excellent! Enjoy the ride!