2001 Ford Escape has blown up 3 egr valves this week...please help my dealer find the problem

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?

BS. The EVR is clearly NOT in the fuel pump, according to the document hellokit posted. Check page 22 for a clear diagram of the EGR system, including the orifice as described by Tester.

I am also suspicious of the fuel pressure claims. High fuel pressure like that would KILL your gas mileage, and cause visibly black sooty smoke out of the tailpipe. I’d get a second opinion before doing it.

I have a few problems with what I’ve read so far.

First, even if the cat were plugged the engine would just die. I’ve never heard of an exhaust system building enough pressure to blow up an EGR valve. This makes me suspect that fuel vapors are getting in there.

Second, I suspect that he fuel vapors and some source of heat energy caused the explosion and that same explosion may have taken out the cat converter. The first stage of the converter is a honeycomb of thin ceramic coated with the catalyst. An explosion could take out the catalyst, and I suspect another one took out the catalyst in the second converter. Blow up that ceramic and it’ll plug the flow through the converter.

In short, I think he’s fixing the results of the explosion rather than the cause. For the cause he may want to look for a reason for raw gas vapor to be entering the exhaust stream and a source of ignition. He needs to start looking at the valves and possible ignition sources.

Oh, and I agree with Bustedknuckles. High fuel pressure would cause rich running and possibly a flooded engine, not an exploding EGR valve and exploded catalyst substrate.

Perhaps another shop…

Thanks for the response, and i think its BS too…and you guys are my second opinion. My third opinion will be tomorrow with my very trustworthy mechanic. The ONLY reason this car went back this particular dealer was to get a replacement cat and EGR valve for free.

I get 15mpg so that is not good…my research into high fuel pressure found this:

If pressure is high and amperage is above specification, check:

? Possible restricted regulator and/or fuel return line

see my repsonse to bustedknuckles…yes another shop is waiting.

And i agree they are just replacing broken parts and not fixing the problem.

Thanks!!!

Cool.

My comment about the valves was thus: if you had an exhaust valve not closing fully, when the piston went up on the compression stroke it would push raw fuel into the exhaust, and when the spark plug fired it’s resultant explosion would propogate right past the valve and out into the exhaust.

I look forward to the shop’s findings.

I’m inclined to go along with an intake explosion rather than a clogged converter.
One would think a plastic vacuum solenoid would blow up or a vacuum hose would pop off before a steel EGR would become uncrimped and scatter.

That fuel pressure is way high and I see no way a used pump, or a new one, would put out that much fuel pressure without there being an underlying fault.
Those faults could be a stuck fuel pressure regulator or a fuel return line restriction.
While the latter is rare it can happen.

My experience with plugged cats is they will idle but absolutely no power.

This drawing shows the Fuel Pressure & Temperature Sensor (FP & T) on top of the engine: http://www.autozone.com/shopping/repairGuide.htm?pageId=0900c152801e8fdd Pull the hose off and see if there is any fuel in the vacuum hose. There should not be any fuel in the vacuum hose. If there is, the fuel pressure signal sent to the engine computer will be in error, and the fuel will go into the vacuum lines to whichever vacuum line, or intake manifold, has the lowest vacuum. The lowest vacuum, in route to the intake manifold, may be the EGR Valve. I don’t have the complete vacuum distribution diagram. Your repairer should have that diagram.
The FP & T Sensor has a vacuum line which, in the usual applications, controls the fuel pressure; but, in your system the vacuum doesn’t control the fuel pressure. The fuel pressure on your car is 70 psi, which is only 5 psi high. The FP & T Sensor vacuum diaphragm may be ruptured. This ruptured diaphragm would allow raw fuel to go into the vacuum hose–and on from there.
You haven’t said anything about the check engine light being on. Is it, and what is the DTC (Diagnostic Trouble Code)? I expect something like P1211, or P1236.
We await your response.

Edited to correct errors caused by lack of data.

my “real” mechanic was too busy to pin down today…i will try again tomorow.

But i will not be having the dealer do anything to this vehicle…

Will you show him this forum on a pc screen, download and printed copy, or rely on a condensed verbal version? Which way contains more accurate details?

the light sometimes comes on…but not while i was last driving it…and there are no codes that can be pulled. We checked.

I showed my trusted mechanic this and i also told him what the dealer said about the fuel pump needing to be replaced. He said that he believes that it is not the fuel pump, but like has been said here a couple times, the fuel pressure regulator.

But he also had a hunch that the fuel presure regulator was a module that was mounted onto the fuel pump and he did not think they could be replaced seperately and if that was the case he thought the dealer should get a crack at replacing it.

I called the dealer and spoke to the service manager and i gently asked him if it could possibly be the fuel pressure regulator and not the fuel pump. He replied that it was indeed no the fuel pump but there was no way to replace just the fuel pressure and agreed that the person who told me it was the fuel pump should have explained that better to me in the beginning. I told him i was going to with hold payment for a week or two in order to verify if it was fixed, if that was alright with him i told him to go ahead and replace the part. He said he understood and would replace it and verify that it was fixed before giving me back my car…

the saga continues…

I can’t find the data, but, I think the engine computer controls the fuel pressure. There is a fuel pressure & temperature sensor on the engine, and a fuel module (in the fuel tank) with which the engine computer controls the fuel pump on and off time.
If I had the factory data, which the dealer has access to, I would know for sure. So, it’s a matter of having the data and reading the data.
If the engine computer controls the fuel pressure, by controlling the fuel pump on and off times, the high fuel pressure wouldn’t be cured by changing the fuel pump. But, if there is a fuel pressure regulator nestled with the fuel pump, that (changing the fuel pump / fuel pressure regulator) might fix it.