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  1. #1

    Default Warm start black smoke

    I've lingered here for a while, but this is my first post. Hopefully someone will have some ideas.

    I have a '99 C2500 Burb with around 80k miles on the 7.4L. A couple of weeks ago I noticed that on warm starts it will crank and crank before it starts up. Sometimes I'll have to pump the gas pedal a couple times. When it finally does start, there is a bit of black smoke that dissipates quickly. On cold starts, it turns over like a champ. No problems what so ever.

    Any suggestions?

    Thanks in advance!

  2. #2
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    Welcome to the site! hopefully another member here with knowledge on the 7.4 will jump in and shed some light on your problem.
    Darcy
    Washington State
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  3. #3

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    black smoke from a gasser??!!!??

    and by warm start you mean if you were to turn the truck off to order at a drive thru or sometihing?

    Ryan

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  4. #4

    Default

    Well, not exactly. It's more pronounced when after the truck has been driven enough to warm up, and then turned off for more than just a couple minutes, even up to a few hours.

  5. #5

    Default

    Quote Originally Posted by RussCrypto View Post
    Well, not exactly. It's more pronounced when after the truck has been driven enough to warm up, and then turned off for more than just a couple minutes, even up to a few hours.
    when was the last time the fuel filter was replaced?

  6. #6

    Default

    Just over a year and 15k miles ago.
    Last edited by RussCrypto; 12-07-2008 at 08:59 PM.

  7. #7

    Default

    hmm, well im not sure
    the black smoke does not come out when driving correct??
    and im not sure if it would help but may wanna change the filter anyway

    somone else will chime in

  8. #8

    Default

    Quote Originally Posted by 04sierracrewcab View Post
    hmm, well im not sure
    the black smoke does not come out when driving correct??
    and im not sure if it would help but may wanna change the filter anyway

    somone else will chime in
    Correct, once running, there is no smoke. It's almost as if a choke plate were to get stuck on a carburated engine.

  9. #9

    Default

    hmm, well could the fule pump be the issue?

    does it run fine when started?

  10. #10

    Default

    Quote Originally Posted by 04sierracrewcab View Post
    hmm, well could the fule pump be the issue?

    does it run fine when started?
    It runs like a champ actually.

    Would a leaky fuel injector cause this?

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