Strange but true…i will keep this as brief as possible and answer questions if i leave anythign important out.
Car is a 2001 Escape with the v-6 auto with 75000 miles.
Up until this past summer it has been pretty reliable…here is the story:
Driving home after the car was parked for a week at an airport and had major acceleration problems. Took it to the deal and he said probably just a cracked coil wire but it seemed fine to hime and he sent us on our way.
Fast forward to recent weeks…when my daughter drove the car from her house to mine and this was the first EGR valve explosion about a mile from our house. Had it towed to the dealer and he replaced the EGR valve and the primary cat and took my 1200 dollars and ssent me home with my “fixed” car. Drove home from the dealer and all was well until the next day when the car was bucking all over again. Called the dealer and he said maybe a coil needed to be replaced but he was certain all was fine. The following week it drove fine for the first 2 days…until the EGR valve exploded.
Called the dealer and he said yeah must be a defective part and he gave me a new one…which exploded after 2 miles.
I am going to drive the car up to him tomorrow and tell him to fix it and i do not expect to be charged for anything until it is FIXED. If i didn’t have 1200 dollars on the table i would never take it back to this dealer.
Help!!!
Plugged catalytic converters ? An exhaust shop can check the flow of the cats.
Just a guess though, no techs in the shop at this hour to confer with.
You took it for repair was told you had a “cracked coil” but the car was not repaired?
Are you being dramatic when you use the word “explosion” elaborate some if you would.
What led to the cat replacement?
You make that statement again “cracked coil” but everything is OK, if you have a cracked coil (can’t picture this),things are not OK.
I can smell all the way through this broadband connection a communication problem.
I am not being dramatic…the first time i was driving down the road, and since i was getting ready to turn the car over to my daughter and it was driving so well, i thought i would get on it a little just to be sure. I was going about 65mph in a semi hilly area and i had the pedal nailed…when i heard this rush of air and i lost power. I pulled over and opned the hood and looked for a blown hose. I saw the EGR valve had a hole in the side.
Second time i was driving down my street after replacing the bloan EGR and i could not get the car to go past 40mph and it had no power…within the first 2 mmiles it did the exact same thing.
So maybe not a complete explosion…but the side blew apart…first for my daughter…and then twice for me.
If it helps the car has never gotten more than 15mpg since we bought it used 4 years ago.
re: cracked coil…the dealer is saying there must be a cracked coil…but he has not been able to find out which one.
re: cat replacement…it was replaced after the first EGR exploded…i’m sure the dealer was thinking that the plugged cat caused the egr to explode. But he never found out or fixed what led to the clogged cat.
re communication problem…i assume you mean betweenme and the dealer? I am telling him everything that has happened, in fact i put it in writing. I am just trying to have him figure out a cause and then fix it. It is my believe he is replacing broken parts, but not able to determine what caused them to break.
While pondering this and trying to connect some dots, I’d just like to clarify that you are talking about the EGR valve.
And not this.
Or this.
http://shop.advanceautoparts.com/ProductDetail.aspx?MfrCode=NIE&MfrPartNumber=FE30001
I conclude the car runs now but with low power and for now a intact egr. You don’t want to damage another egr,It sounds like this will happen if you drive to Dealer.
I would want to know what amount of manifold vacuum we have. The “explosions” must be gasoline (raw or vapors) getting into the egr,how I don’t know. These secondary ignition issues (cracked coils) must be resolved. Is the Dealer willing to put some one on the car to get to the bottom of this? is payment a problem?
yes it is the egr valve 
no…the current egr valve blew a hole in the side. And i called the dealer and he said to drive it in because he does not have a way to tow it. which the car does actually drive better once the hole happened.
I agree with Oldschool about raw fuel getting into the valve. Perhaps this would mean one of the coils isn’t working and the fuel mixture is going out the exhaust. This would explain the damaged CAT also. Checking the operation of the coils with a scope would be very easy to do. I guess a leaking injector may cause the trouble also.
I’m still undecided on this one as I’ve never heard of an EGR valve blowing apart even on an engine with a clogged converter. Much less doing it repeatedly.
Checking for an exhaust restriction could be easily done with a vacuum gauge just to weed that scenario though.
Question. Is there any kind of pop, thunk sound, etc. right before this EGR problem occurs? I’m just tossing around the possibility of a minor intake explosion due to a leaking fuel pressure regulator at the moment in time when the EGR valve is open.
(Yes, I’m grasping a bit.)
Also, does the vehicle seem to run well until this happens or are there any stumbles, erratic idle problems, etc?
It looks like it’s wild theory time. For an explosion to occur, there has to be fuel and air containing oxygen. How could both fuel and oxygen get into the EGR valve? Vacuum acts on the EGR valve and the EGR pressure sensor. The vacuum source starts at the engine intake manifold, and gets distributed around the engine via lines and hoses. Because of varying restrictions in the lines/hoses, the vacuum won’t be the same in all.
What are the possible fuel sources? The fuel pressure regulator has a vacuum hose attached to it. If the fuel pressure regulator diaphragm were to leak, the fuel would go into the vacuum lines/hoses and on into the intake manifold; except, if it didn’t go directly. If a line/hose had less vacuum, say on one side of the EGR valve, or EGR pressure sensing valve, the fuel/air could get to the hot EGR valve, and KA-POWIE!
Same possible scenario with the charcoal canister purge —which is a vacuum hose, right?
if raw fuel were getting into the egr valve, when it tore a hole in the side of the egr valve this fuel would be visable and smell when iopen the hood, and or continue to drive. I am going to suggest you guys eliminate raw fuel from the equation. i think its a combination of heat and presure that is breaking the egr valve.
there is no noise…just the sudden sound or air whooshing…
first time for me the car was driving well…so i put my foot into it to see if i could cause somerthing/anything to happen that would prevent me from giving it back to may daughter…this caused or contribited to the second egr valve blowing up. The first egr failure i was not in the car.
The third egr failure was right after the second, and the car did not run well…very much restricted…and i was going about 40mpr at low rpm’s and the egr valve gave up.
i will say that the EGR was extremely hot after i pulled over…too hot to touch.
The EGR system in your vehicle is a differential backpressure induced EGR valve system. Which means some of the exhaust backpressure is used to force the EGR valve open. To control the pressure and volume of the exhaust gasses that enter the EGR valve, the feed pipe from the exhaust pipe to the EGR valve has an orifice that controls the amount of exhaust gasses that enter the EGR valve. If the orifice in this tube is no longer there from corrosion or is just burned away, too much exhaust gas enters the EGR valve destroying it. This will occur when the engine is under a heavy load because the backpressure is at it’s greatest, and the exhaust temperature is at it’s greatest. If there’s a restriction in the exhaust system, such as from a restricted catalytic converter or a restricted muffler, this will make the problem much worse.
So, make sure there’s no excessive backpressure in the exhaust system, and change out the feed tube from the exhaust pipe to the EGR valve to make sure there’s a good orifice in this tube
Tester
i will mention this to my “dealer”…thanks!!!
When i replaced the egr valve i did not notice any “oriface” at the opening to the feed pipe. Would i notice anything?
No. If you look where DPFE sensor is connected on this tube, that’s where the orifice is located. And you can’t see down the tube to see the condition of the orifice.
Tester
Go to this pdf, and scroll down to page 22 to see the diagram of the EGR system: http://www.motorcraftservice.com/vdirs/diagnostics/pdf/obdsm986.pdf It shows the EVR (EGR Vacuum Regulator) which I theorize, if its diaphragm had a hole in it, could allow fuel-rich intake air (partial vacuum) to reach the EGR valve.
At any rate, all the parts which operate on, and with, the EGR valve need to be checked for proper operation. This includes checking the tubing for carbon build-up, and the orifice opening for being open.
You can download, and print, these pages for “clarification” for your repairer. I hope they are receptive.
UPDATE;
I dropped it off at the dealer monday and they confirmed that the cat had indeed replugged up, and that they needed to replace the cat and egr valve and take some readings. No charge so far…so i said go for it. I also told them that in the research that i had done, that it was suggested that a possible thing for them to check would be the oriface in the EVR. He thanked me for this advice and said he would check everythign and find the problem.
I got a call tonight and he said that in a 2001 escape the EVR valve that i mentioned was actually inside the fuel pump. He also said he found the problem…he suspects it is the fuel pump because the fuel pressure reading he took was at 70 and it he said it should never be above 30. He quoted me $380 for a replacment fuel pump, and offered to throw the 2 hours of required labor in for free. Again i thinked him for his findings and that i would discuss it with my wife tonight.
So since my wife knows nothign about cars…i am throwing this out to you fine gentleman…what do you guys think?