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Underfueling and noise from the fuel pump

Discussion in 'A3/S3 Forum (8L Chassis)' started by spiker, May 23, 2010.

  1. spiker
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    spiker usually growling at something

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    Hi

    engine management light on - Vag com reports underfueling and whine from fuel pump intermittently

    Fuel pump changed - noise still there
    Maff changed
    Thermostat and temp sensor changed
    Fuel filter replaced

    Still no better

    Dis reports 42mpg overall !! which is inaccurate - checked based on last fuel load and was actually getting 29mpg

    This has been going on for 6 months now and I know i should just take it to audi ( my local garage is not very s3 friendly ) but i am trying to avoid the dreaded dealer rate

    Any suggestions much appreciated

    Cheers
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  2. Andrew@A.L.D
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    Andrew@A.L.D Cylinder Head Master

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    Have you checked the fuel pressure?
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  3. spiker
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    spiker usually growling at something

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    How is that done ?
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  4. Andrew@A.L.D
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    Andrew@A.L.D Cylinder Head Master

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    some of your local fuel injection specialists should be able to help
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  5. <tuffty/>
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    <tuffty/> Badger 5 Edition Staff Member Moderator

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    Could possible be a problem with the fuel pressure regulator (FPR), check the vacuum hose coming off the FPR which is on the right hand side of the injector fuel rail.

    Could do with being logged tbh, You are not too far away from Badger 5 (J13 M5)... might be worth giving Bill a call, he would be a lot cheaper than a dealer :)

    <tuffty/>
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  6. sportstractor
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    sportstractor Chugger

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    was also going to suggest fuel pressure regulator.

    Ha my local Audi garage dont seem to be S3 friendly either, they seem fearful of the thing
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  7. Welly
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    Welly VX220 SC Driver :)

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    Thats because, IMHO, Audi Mechanics know as much, or less than, your average work a day mechanic.

    They are the same old bodgers in nice overalls.
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  8. Welly
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    Welly VX220 SC Driver :)

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    Agree. Does the fuel pump still whine, even though it's been replaced?

    The FPR being shot would explain the whine of sorts - it is probably being over worked due to fluctuating pressure requirements.
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  9. spiker
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    spiker usually growling at something

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    Cheers guys - FPR next then

    Do you have any contact details for this 'badger' ?
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  10. sportstractor
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    sportstractor Chugger

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    its badgerbill on this forum
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  11. <tuffty/>
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    <tuffty/> Badger 5 Edition Staff Member Moderator

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    #11
  12. spiker
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    spiker usually growling at something

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    The Badger discovered a knackered FPR , replaced the top lambda , fuel filter and blew out the pipes
    Strange black residue coated the FPR - which turned powdery when dry - no idea how it i got in there or what it was

    So all sorted -
    #12
  13. Welly
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    Welly VX220 SC Driver :)

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    Glad it's sorted, I saw it up there and thought she may have a knackered FPR.

    Could be residue from contaminated fuel - there was a big thing a long while back where Tesco sent a batch of fuel out contaminated with Silicone and it shagged a ton of Lambda sensors.

    Could be something similar - I've had dodgy fuel before (normally always from Texaco - AVOID!), when emergency filling with sh**ty fuel.
    #13
  14. spiker
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    spiker usually growling at something

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    I try and avoid supermarket fuel , on the odd occasion i use if i have no choice but usually just to get me to shell

    I remember those issues a while back - shame there's nothing I can do about it
    #14

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