Question about 2004 Mercury Mountaineer

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Service engine light on mechanics machine read code po456 emmission leak new gas lid was put on two weeks ago light went off for back on in febuary I had the same thing the shop found a pin hole in one of the gas lines close to the tank 450.00 later the problem returns.I want to know if this problem is unusual and how can I get around not flipping the bill again.

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It can simply be the gas cap is not screwed down after the last fillup. Remember too that you need to clear the computer code or it will take 25 to 50 startups to cycle the code out of the system. Autozone or Oreillys scans for free and can wipe the memory of the computer for you. Check for a clamp on the fuel fill which joins the filler to the large tank hose. Its under the wheel well.

Since you wrote about the Febuary service, March, April, and some of May could be within 90 days. Also Emission parts are usually covered by Law for a longer time period. You should check by calling Ford, Lincoln, Mercury Customer service and asking about the earlier replacement part(which parts are covered, if its one of them). You may be able to recover some of that $450, especially if a Dealer charged you for a covered repair.

What the repair facility needs is a "smoker" machine which reveals leaks. There is also a solenoid which opens the vapor canister to draw out fumes. The repair shop should test the part they installed to see if it was defective. There have been several reports to Fixya about Mice eating wiring and chewing hoses. This applies to all models of vehicles.

Posted on May 10, 2010


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Posted on Jan 02, 2017


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