Question about 2004 Ford E250

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I have a Ford E250 4.6V8. While accelerating the A/C vents in dash cut out. The vent goes to either defrost or the floor. I took this van to a mechanic, they smoke tested the vacuum lines. The lines tested fine. The mechanic seems to think it might be the check valve or vacuum ball. The cost for labor being $1,000 since it is located behind the heater core. Has any one else experienced this? Any ideas on any other solutions? Thanks!

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  • tammy_alford Jul 12, 2009

    The A/C blows from the main vents in the dash, but when I accelerate the air blows from the defrost or the floor vents. Air flow will eventually return to the main vents, but only after a few minutes pass. I have tried turning the A/C switch off and then turning it back on, and this will bring back the air flow some of the time, but not all of the time. I am trying to solve this problem on my own to avoid the mechanic's hefty fees. I'm not completely confident in the mechanic's diagnosis, so I was wondering if anyone had any other ideas as to what it could be? Any suggestions, or thoughts would be greatly appreciated, thanks!

  • Ned C Cook
    Ned C Cook May 11, 2010

    That is ludicrous.. I'll ponder on this one, heavily



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Usually the check valve is in the engine compartment. look on the pass side at the heater box and see if the vac lines have a check valve in it it should be a grey or black line

Posted on Jul 11, 2009


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I had the AC problem too, and they said there was a hole in the hose. They fixed it and now it comes out of the vents as it suppose too, but when I first accelerate to go up a hill, it stops blowing out of the dash vents. Once I have stopped going up the hill, the air starts blowing out again. Weird.

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