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Throttle Body Vacuum leak, worth fixing?

Discussion in 'Car Repairs / Maintenance' started by industryspark, 11 Feb 2009.

  1. industryspark

    industryspark

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    Following on from a previous post i would like some more advice if someone would oblige.

    Polo 1 litre which is hesitating on acceleration and has a small loss of power. I had a mechanic replace some faulty tappets which now sound loads better. He mentioned a further problem on the car though which he described as a 'flat spot' on the throtle body which would cause the lack of acceleration. As it was late and i was rushing i didnt really have time to talk further with him.

    The tappets been fixed seems to have improved the cars performance but the hesitation/loss of power is still there, not as bad however.

    Can anyone expand on what 'flat spot' may mean on the throttle body? im presuming it may mean the gasket needs replacing as there is a vacuum leak?

    also is there anyway of testing see where the leak is, apart from physically feeling? and would such a vacuum leak give me the symptoms of hesitation?

    Can i just replace the gasket on the underneath of the throttle body and not the whole throttle body?

    regards.
     
  2. Belle427

    Belle427

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    It could be a simple gasket or split pipe somewhere,it would need to be fixed as this can cause the rough running your experiencing.
    Try spraying some wd40 on the area you think the leak is,you should notice a change in engine speed if there is an air leak
     
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  4. industryspark

    industryspark

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    Hi, thanks for the suggestions

    The frustrating thing is that the problem is really distinctive. The car runs fine for 2-3 minutes and then suddenly it loses the ability to accelerate quickly as it should. I would say the acceleration ability is halved. I cant afford to have it looked at again so im having to go through things myself.

    Im thinking that the problem occurs when the engine gets warm which accounts for the 2-3 minutes of running ok.

    Im sure there is someone out there who knows what the problem is as to me it seems distinctive.

    I have a few ideas of what to try which im hoping to work through-if anyone can comment on why they believe it may be something or if they think they can distcount one of the things im going to check then please comment-the problem is starting to do my head in! :mad:

    Im thinking problem could be

    1, Fuel filter - 64,000 and never been changed, worth checking i think but if it was this why would the car run ok for a few minutes?

    2,Fuel injector - Possibly one blocked/partially blocked? But again why ok for a few minutes

    3, Vacuum leak at throttle body - as stated previously this needs attention, but again why would this problem occur after a few minutes running

    4, Lambda sensor - dont know much about these so any suggestions welcome

    What im really after is if someone who knows a bit more than me could point out things that would be effected after a few minutes running, like i said-this seems like a decent clue to me, just dont know what :cry:

    Thankyou
     
  5. Belle427

    Belle427

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    You need to fix the air leak as this will most probably be causing problems with the fuelling,the coolant temp sensor is worth changing too if you have not already done it
     
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  7. rottie007

    rottie007

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    also the car is probably "on choke" or the fuel injected equivalent at first which is why its ok till its warmed up

    change that fuel filter would be my first suggestion..
    then as said above get some wd40 around the throttle housing it iwll show up the leak
     
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