Question about 2004 Jeep Wrangler

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Check engine light code PO456

My check engine light went on in my 2004 jeep wrangler, I looked up the code, PO456, it said very small leak has been detected in the evaporative system. I changed the gas cap and the light still came on. This has been a problem for a while, it goes away for a while and then it comes back on a few days or even weeks

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  • hp5230 Feb 27, 2009

    can you tell me if it is a big job to fix?



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Most likely the pressure sensor in the fuel tank for the evap system is defective.

Posted on Feb 26, 2009

  • yadayada
    yadayada Feb 27, 2009

    On a car lift no big deal, on the ground it can be difficult, the sensor is on the top of the tank in a rubber grommet, it is about the diameter of a tube of tooth paste with of course a wiring connector on it.



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What does the code po456 mean?

Usually this P0456 code is caused by an incorrect or faulty gas cap. Filling the fuel tank with the engine running could conceivable cause this code as well or if the cap wasn't properly tightened. Any of the following could also be the cause:

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* The EVAP Canister may be leaking

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PO456 code on 2002 Jeep Wrangler.Where do I start?

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Trouble code po456 evap small leak ? could it be the gas cap ?

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