Question about 2000 Jeep Grand Cherokee

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P1494 code hi my check engine light came on so we thought it might be the gas cap so we replaced it and had the light turned back off well it came on again and gave this code i looked it up and it says leak detection pump switch or mechanical fault so what exactly does that mean? what do i have to do to fix it and how much do you think it would cost thanks Beth

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  • bcripps Aug 07, 2008

    same as beth

  • Anonymous Mar 21, 2014

    I just want to know how much would all this cost



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It means you aren't tightening the gas cap down tight, or the vent in the gas cap isn't sealing. Open the gas cap, and look at the center. Take a punch and jiggle the center, which is a valve. This will usually re-seat the valve... or replace the cap. Every so often the computer will pump air into the fuel tank to determine if there's a poor seal in the air space above fuel. If it doesn't find pressure holding, then the error code is logged.

Posted on Aug 08, 2008


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