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

245678

Comments

  • edited February 2009
    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?
  • edited February 2009
    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.
  • edited February 2009
    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.
  • edited February 2009
    i will say that the EGR was extremely hot after i pulled over...too hot to touch.
  • edited February 2009
    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

  • edited February 2009
    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?
  • edited February 2009
    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
  • edited February 2009
    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.
  • edited February 2009
    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?
  • edited February 2009
    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.
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