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Thread: Underpowered When Starting Sometimes

  1. #1
    Junior Member LimitedRunDouglas's Avatar
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    Underpowered When Starting Sometimes

    Sometimes when I start the car and drive it feels underpowered like it won't rev up high enough. The car accelerates much slower when this happens.

    Am I starting the car wrong or is this a sign of something more serious?
    Proud Owner of 16677

    Twitter: @limitedrundoug

  2. #2
    Senior Member DMC5180's Avatar
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    Manual or Automatic?
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  3. #3
    Senior Member DavidProehl's Avatar
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    Do you still have the original fuel pump and hoses? It could be a collapsing fuel pickup line although that should feel more like a stutter as though the tank was empty rather than just unable to accelerate.

    Clogged injectors or plug wires mismatched would also reduce power, but that wouldn't be sporadic, that should be consistent.

    Another thing to look at is your throttle spool. Can you manually rev the engine by pulling on the spool? Does it feel or look like it is or could be catching on something that prevents it from revving further?

    Those are the few things I'd look at first but I'm sure there are a host of other possible causes others can recommend.
    David Proehl

  4. #4
    Junior Member LimitedRunDouglas's Avatar
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    It's a manual transmission.

    The throttle spool seems fine. Again it's weird as this isn't an all the time thing. It happened today but I assumed it was because it rained really bad and I had the car in the parking lot. Normally I won't drive it on rainy days.
    Proud Owner of 16677

    Twitter: @limitedrundoug

  5. #5
    Senior Member DavidProehl's Avatar
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    If it happens after washing the car or after rain, then it likely is poorly fitting spark plug wire boot seals or aging injector seals allowing water to get in.
    David Proehl

  6. #6
    Senior Member Bitsyncmaster's Avatar
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    Your mixture is rich on a cold engine if you have adjust the mixture via dwell meter to book values and your cold pressure regulator is working as designed. So first thing to do is adjust the mixture on a hot engine via book values.
    Dave M vin 03572
    http://dm-eng.weebly.com/

  7. #7
    Senior Member
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    Two common, possible causes. A problem with the Control Pressure Regulator (CPR) or a problem with the Lambda system if it feels fine once it warms up. If it is "missing" ie, not running on all 6 cylinders it could be a problem with the secondary ignition system. It is normal for the car to run a bit 'off" till it warms up a little.
    David Teitelbaum

  8. #8
    '82 T3 FABombjoy's Avatar
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    If the vacuum enrichment isn't working properly on the WUR these are the exact symptoms. Like, you can go but it hesitates a bit and takes time to climb in RPM.

    Especially if it gets better as the engine warms up.
    Luke S :: 10270 :: 82 Grey 5-Speed :: Single Watercooled T3 .60/.48 :: Borla Exhaust :: MSD Ignition :: MS3X Fully SFI Odd-fire EFI :: DevilsOwn Methanol Injection

  9. #9
    Junior Member LimitedRunDouglas's Avatar
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    Just went to try and start the car.

    It felt weird and when I hit the gas, it actually felt like it was going to stall out in neutral. I pushed down a bit further a few more times and it finally started reving up like normal and seemed okay after.

    Going to try a few more tests.
    Proud Owner of 16677

    Twitter: @limitedrundoug

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