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A Strange Boost Issue Noticed While On A Spirited Drive Yesterday...

Discussion in 'A3/S3 Forum (8L Chassis)' started by S3 Paul, May 30, 2011.

  1. S3 Paul
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    S3 Paul Well-Known Member Regional Rep

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    [May 30, 2011]
    While on a bit of a random road trip yesterday a few of us decided to go to Skegness for fish and chips...
    While on route there was a couple of moments when i was on the throttle then backed off for a split second then back on the gas only to feel no boost for a second or so... while this happened the boost gauge showed vacume rather than boost, But then like somebody flipping a switch.... full boost again,
    Not realy a massive problem but would like to know what is wrong/ failing??
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  3. jojo
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    jojo S3 Drift King! Staff Member Moderator

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    [May 30, 2011]
    Vacuum leak, MAF Sensor, knackered DV?

    Best to do a scan and some logging with Vagcom to see what comes up first.
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  4. S3 Paul
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    S3 Paul Well-Known Member Regional Rep

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    [May 30, 2011]
    I scanned the car on returning home but no faults found.
    What blocks if logged would show something untowards?
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  5. jojo
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    jojo S3 Drift King! Staff Member Moderator

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    [May 30, 2011]
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  6. S3 TAM
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    S3 TAM Pocket now empty

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    [May 30, 2011]
    Sounds like high EGT's and the ecu is dumping loads of fuel in and cutting boost.

    FMIC should solve this.

    I might be well off tho. Just sounds like an issue i have/had.
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  7. <tuffty/>
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    <tuffty/> Badger 5 Edition Staff Member Moderator

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    [May 30, 2011]
    What boost did it show prior to the cut? I have had this when I had a boost pike shortly after changing my FMIC... it was hitting 2bar at the time of course but sounds like the ECU pulling back the throttle...

    <tuffty/>
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  8. S3 Paul
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    S3 Paul Well-Known Member Regional Rep

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    [May 31, 2011]
    I have a FMIC for around a year now too,
    Erm the car runs 20 to 22 psi unless its very hot then 19 to 20
    The needle just sat in the vacume area then after about a second was back to 20 psi
    The car did feel like it held back too. So i know it wasnt a sticky gauge.
    Not a major issue on its own but if its an indication something isnt right... i would love to track it down.
    #7

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