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

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Comments

  • edited February 2009
    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.................
  • edited February 2009
    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
  • edited February 2009
    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!!!
  • edited February 2009
    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.
  • edited February 2009
    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.
  • edited February 2009
    My experience with plugged cats is they will idle but absolutely no power.
  • edited February 2009
    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.

    [b]Edited to correct errors caused by lack of data.[/b]
  • edited February 2009
    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...
  • edited February 2009
    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?
  • edited February 2009
    the light sometimes comes on....but not while i was last driving it...and there are no codes that can be pulled. We checked.
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