The DPFE is referenced as the EGR Transducer in this illustration

 

I too am getting the 402 code. I know that there has been quite a bit of discussion on this issue, but I would like a bit of clarification, since this will be one of the first "fixes" I tackle on my own with my new (used) truck (4.6L).

Does this code point to the EGR valve replacement or the DPFE?

Is there a way to know which is needed to be replaced or do you guys recommend replacing both. If it is the EGR valve that I should replace, what is the proper technique for getting the metal fitting on the back off? Can this fix be done with the throttle body still on the manifold? What about the DPFE, which seems to be straight forward, should that be the first line of defense?

What about the discussion (and pictures) of the EGR thingamijigs that have the carbon "ant hills" on them. Where exactly are these? Is this repair and/or cleaning more indepth and does it require removal of the throttle body?

Sorry for the multiple inquiries, most of you are far more experienced than I am when it comes this stuff. But I sure do appreciate this board. Working on my boat engine with a traditional four barrel and manifold seems much easier.

 

Macman2,

I want to pass on a recommendation that I received from one of the wise, old motorheads I received when I first subscribed to this site. Go to the local Auto parts store and buy a Haynes Maintanence Manual for your model year. This manual is very in depth with lots of pictures and instructions from the basic tune ups to major overhauls. I bought mine at AutoZone for $15 US dollars. Then keep your ear to the ground to this site and you'll see that most of the suggestions here are fairly easy to do with the help from the manual. Also, you'll catch on to the jargon in no time! Enjoy!



Dave

 

Spuzzly

You are right on. I just purchased a manual on CD. It is a Ford Factory DVD that I picked up on Ebay. I will also probably go by the Parts shop and pick up the hard copy. That will be easy to have with me out in the garage. Thanks.

Any thoughts on the EGR vs. DPFE??

 

Code 402 is an excessive amount of flow which either means the DPFE is bad or the vavle is sticking open longer than it should. All my money (which is not much) is on the DPFE being bad. Your Ford DVD should show you how to test )backprobe) it with a DMM (digital multimeter). If not I'm sure the Haynes explains it simply and it is simple to do providing you have the multimeter. I used three little needles to probe the back of the connector and laid the contacts of the tester on the needles, (the test probes tend to be a little to big to backprobe with).

The "ant hills" you speak of is the carbon build up of the two passageways in the TB. If you are havinga EGR code, I would advise you to remove the TB and clean with a TB cleaner. (make sure it is coating safe). It seems hard but it's not that bad, just take your time. A new gasket is not required as it is a graphite coated gasket and in some cases is good enough to reuse. Mine was a little brittle and one cornor chipped off in the reinstall. A new TB gasket (probably called a upper intake gasket in the parts books)is less than 6 bucks. You will need to remove the EGR valve which takes like a 1 1/8 or 1 1/4 wrench, clean this while off. Don't forget a new EGR valve gasket.

Let us know if you need more info.

 

Not to beat a dead horse, but I have a 2002 with 13,500 miles on it and my sensor went bad on this past Tuesday as well. Autozone also pulled a 402 code from the SES as well. The service department made it sound like they expected it to go bad. They fixed it in 1.5 hrs.

 

Boss, If the EGR IS dirty you will need to find where the problem is first. Yes the DPFE Sensor is known to clog up. These coarroad on the inside and plug up. Ford has corrected this problem by making them out of plastic instead of alluminum now.
To ck the Sensor you will need a digital volt meter. What you do is backprobe the signal wire and see if it changes while blowing into the inlet port of the sensor, simulating exhaust backpressure. I use a section of hose to do this test.

Check the hoses that connect to the sensor for blockage also. Be carefull when handling these hoses as they are made of silicone and can tear easily.

There are also passages that are in the throttle body adaptor that tend to clog. This requires removal of the throttle body adaptor from the upper intake so the passages can be rodded out. But You can check these passages before removing the adaptor by disconnecting the EGR tube that leads to the EGR Valve and test the flow of air through the valve and thus through the hidden passages inside the TB adaptor. To do this use a hose that fits the passage where the tube went so you can blow into it. You must also apply vacuum to the EGR valve so as to hold it open for this test. If the passages are dirty you will find it difficult to flow air into this port.

 

I did it! I went ahead and bought a new DPFE from my local dealer for $80 and installed it (20 min.) and reset the light and all is fine now. To think that the dealer wanted $220 to $250 for this makes me wish I had come to this site much sooner fopr other minor stuff. Oh well, now I am ready to tackle many more repairs that will save me $$$ and allow me to enjoy the satisfaction of doing it myself.

$80 DPFE
$14 Haynes Manual
$00 OBDII loan from parts store
________

$94 vs. $220 or more!!!!

Thanks guys

 

Here is another way to save yourself some money when purchasing FORD PARTS go to www.fordpartsonline.com depending on what you need the prices over your local dealer are usually much less even with the shipping charegs which tend to be pretty resonable. I just purchased some torsion bars from them and saved 30.00 per bar . You do need to use Microsoft Internet Explorer to navigate the website properly.

Richard D.

WHILE YOUR HERE CHECK OUT MY GALLERY:
https://www.f150online.com/galleries....cfm?gnum=2479

 

Richard D

1. http://www.fordpartsonline.com/ link is not working.

2. Why new torsion bars already?

BTW great looking truck!

 

Link works fine for me try using Microsoft Explorer sometimes it will only work with that I just clicked it and it took me right to it. The reason for new torsion bars is I am upgrading to a heavier duty torsion bar. It is a beefier bar than what came stock on the truck. Thanks for the compliment it means alot since I have put a lot into my truck and am still doing so.

Richard D.

WHILE YOUR HERE CHECK OUT MY TRUCK:
https://www.f150online.com/galleries....cfm?gnum=2479

 

Tried to search for the DPFE valve out of curiosity, and could not seem to pull it up on the website. Any ideas on how to better search on their catalog?

 

Try looking under emissions, intake, exhuast they have an 800 number here it is you can always call them 18005492005

Richard D.

WHILE YOUR HERE CHECK OUT MY GALLERY:
https://www.f150online.com/galleries....cfm?gnum=2479

 

Another idea that has actually worked for me. I had a Ford dealer match the price of a part from fordpartsonline. Granted most will often not do it but mine hadn't heard of the site and thought it was pretty interesting. I didn't even really ask them too, he just sort of offered. If it's something I can't fix it goes right to them. So far they have been fairly good to me except for the wrong price quote on a plug change once. I feel business are more likely to help you out when you frequent their place.

 

DPFE? That's one I didn't know either! Thanks for the info.