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ttiger79, Auto mechanic
Category: Ford
Satisfied Customers: 1257
Experience:  ASE Master Certified, Advanced Level Engine Performance
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2002 Ford Escape: V6..EGR valve..the check engine light keeps coming

Resolved Question:

I have a 2002 Ford Escape with the V6 in it. I have had every sensor on the EGR valve replaced over the last few days because the check engine light keeps coming back on. I spoke with the mechanic today and he said he replaced one that he replaced again the other day. i am not sure which one it is but he said that it is supposed to read .5 to 1.3 or something on voltage. . He replaced the other one that he had just put on two days ago. he said when he ran computer the one he had replaced two days ago is now only reading .02 so he went ahead and put a new one on and it read 1 volt. He drove it 25 mi. came back and said it was fine. I drive it 5 mi. and the light is back on again. Does anybody have any idea what this could be? It is to my understanding that this part has three or four different sensor's on it and we have replaced every one of them. I called the mechanic to tell them that I was bringing it in again. They seem to really have no idea how to diagnose it. Please help. Thanks!
Submitted: 9 years ago.
Category: Ford
Expert:  ttiger79 replied 9 years ago.
Do you know what the diagnostic trouble code is that keeps coming up? I know what sensor you are talking about, but the code number would be about the only way that I can correctly point you in the right direction.
Customer: replied 9 years ago.
Reply to ttiger79's Post: No I really don't. They said there is nothing besides these EGR sensors that are pulling up on the computer. It has happened tomorrow will be my 5th time that I will be going back.
Expert:  ttiger79 replied 9 years ago.
I can give you some information.

The sensor you are speaking of is the DPFE (or EGR pressure) sensor. This is a very high failure part on the Ford vehicles. They have a few different styles of this sensor, all do the same thing. This, however, is a factory recalled part. If you have been paying for replacement, you shouldn't have had to. The shop should have informed you of this recall. Here's a copy of an owner's letter:

This sensor will also not cause a specific code to be stored. I'm going to venture a guess and say that you have a P0401 code stored (EGR flow insufficient.) This is the code that we usually see on these cars. And yes, key on, engine off, you should see right around a 1 volt signal from this sensor. I would not recommend an aftermarket sensor on this, either. I've installed 4 bad aftermarket DPFE sensors on an Explorer in the past. Got a dealership sensor, and it was fine.

There are other things that can cause this code, too. If the EGR valve has failed, this code can be set. If the EGR passages are plugged, this code will set. The only way to check this is to remove the EGR valve itself, and look into the passages.

I would recommend asking if this was the sensor that was replaced, and if it was, ask why you were charged for it. If you can get me a code number- even tomorrow- I can give you a much more detailed description of the problem.
Customer: replied 9 years ago.
Sounds good. So even on the 2002 it was a recall? May be the reason they have been willing to absorb the cost the last two times since it was a recall. Does a mecahnic shop have to check and see if it was a recall or do you think it was an honest mistake. I will see if I can get you a trouble code tomorrow. I will speak with you either way. Was there a recall on all 3 or 4 sensors or just the one?
Expert:  ttiger79 replied 9 years ago.
There really is only one sensor for the EGR system- that is the DPFE sensor. This sensor tells the computer the amount of EGR flow is going back into the engine. If it fails, it defaults to an EGR low flow code.

I looked into the recall a little more, and it extends the warranty of this part up to 5 years or 60000 miles, whichever came first. So depending on the mileage on your Escape, you may have not qualified for replacement. Maybe that's why they didn't mention it. I don't know the mileage on your car.

Definately get me the code tomorrow, and I can tell you where to look to solve this problem!
Customer: replied 9 years ago.
Well, I went back this morning and they said they are not going to be able to fix it, and that I will need to go to the Ford Dealership and have a Z1 test done. They said the code was 402 EGR flow excessive. They have replaced all three sensors..two of them were dealer snesors and only one was aftermarket, it was made by standard(small rectangle with wire clip on side) say's VL150, 07193. They also said they blew all the passages out. My vehicle is an 02 with 59, close. I can get you a pic of the part if necessary. Thanks for all of your help! Oh and he also mentioned something about there being a little bit of moisture in there..mechanic said "I don't know if that is normal or not. That is all I have. Thx.
Expert:  ttiger79 replied 9 years ago.
That helps!

The diagnostics for a P0402 are exactly the same as a P0401. The description you have is correct- EGR excessive flow. Here's a diagram of the entire EGR system:

There is only one sensor in the entire system- the DPFE sensor. This sensor is most likely going to be the problem- again, unless the shop is talking about the EGR solenoid as being one of the sensors?? There's one sure test for the EGR valve and the EGR passages, though. If you apply vacuum to the vacuum port on top the EGR valve itself with the engine running, the engine should almost stall. This would indicate the valve is functioning correctly and the passages are clean.

All signs point to the DPFE sensor, though, and I think the dealership will tell you the same thing. At that mileage, take it in to the dealer and get it fixed for free!!

The moisture is going to be normal. When the check engine light is on for the EGR system, the EGR is disabled until the system is repaired and the light is turned off. During the time it's disabled, the moisture will build in the passages. Perfectly normal.

Let me know if you have any more questions!
ttiger79 and 5 other Ford Specialists are ready to help you
Customer: replied 9 years ago.
Reply to ttiger79's Post: I think that was it! I had it replaced and my light has stayed off. I appreciate your help!