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Hissing fuel cap

Discussion in 'A4/S4 forum(B5 Chassis)' started by Broken Byzan, Jan 23, 2008.

  1. Broken Byzan
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    Broken Byzan Photographic Moderator Staff Member Moderator

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    I have noticed my fuel cap hissing lately, and have narrowed it down to the breather system.When the car switches over and stsrts pulsing the solenoid the car drops its revs and starts to run poorly for 30 secs or so then clears. I recon the charcol cannister is dodgy, so what i am saying is a) has anyone else had this as a problem and b) does anyone have one i can have etc etc

    Thanks
    Mark
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  2. madvw
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    madvw Active Member

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    the fuel system is closed system, and the hissing from the cap maybe due to a worn out fuel cap.
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  3. Broken Byzan
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    Broken Byzan Photographic Moderator Staff Member Moderator

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    Yeah that and when the car activates the little solonoid on top of the airbox, the car idles funny for a short time then clears.So i was thinking it wasnt working properly when it swaps to the closed loop, hence a dodgy carbon thingy.

    Sound right????
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  4. madvw
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    madvw Active Member

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    but isn't it hissing from the fuel cap? that suggests that it isn't sealing correctly.
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  5. Broken Byzan
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    Broken Byzan Photographic Moderator Staff Member Moderator

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    Yeah, but my thoughts are if its hissing there, it isnt breathing properly through the rest of the system ????? As the seal etc looks intact and i always click it yp when doing it up
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  6. joost
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    joost Active Member

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  7. Broken Byzan
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    Broken Byzan Photographic Moderator Staff Member Moderator

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    :icon_thumright:
    I shoulda known better and searched :asskicking:

    Interesting, although my solenoid seems to work etc ok

    I am willing to try it, anyone have a working spare??
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  8. filipharvey
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    filipharvey Amusing Tagline

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    Had the same problem on mine, got a replacement from a Passat in a scrappy, different part number, but they are all the same.
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  9. Broken Byzan
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    Broken Byzan Photographic Moderator Staff Member Moderator

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    Cap or N80 valve ??????????
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  10. filipharvey
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    filipharvey Amusing Tagline

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    Sorry, the valve! Clear as mud me!
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