Car runs rough, fine before

Discussion in 'Engine Topic' started by Vince's79, Jun 29, 2010.

  1. Vince's79

    Vince's79 Member

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    Let me give the full rundown...

    The engine is a 350, holley 750, high rise manifold, headers, and a street/strip cam. The engine always ran really well but one day I drove the car three times. The first two times it ran perfect. The third time (late in the day), I start it up and it wants to stall on me. The idle was very rough but it was fine high in rpms.

    I took the fuel filter off and there was no junk in there. I took the fuel bowls off and cleaned everything out. I took off one of the plugs and it was slightly white. I started it back up and the car ran better but still not like it was (it would die out in gear). Then I found a vacuum leak where I put the fuel bowls back on. I got a new gasket for the fuel bowl and metering block and put it back on. I start it and it runs worse then ever. There was white smoke coming out of the dual exhaust and it has never done that since the rebuild.

    Is it possible by fixing the vacuum leak it threw something off in the carb? What other things can I do? Thanks in advance
     
  2. CamaroMan79

    CamaroMan79 Veteran Member Lifetime Gold Member

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    White smoke form the exhaust usually means the engine is burning coolant. Either a bad head gasket, a cracked head or a cracked block.
     
  3. Vince's79

    Vince's79 Member

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    I'll run a compression test on it and pull the plugs. It rank fine when I pulled it into the driveway though and the exhaust is true dual and smoke is coming out of both pipes.
     
  4. 79HumbleBee

    79HumbleBee Veteran Member Lifetime Gold Member

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    i had a similar situation to this not too long ago after a transport company moved my camaro. secondaries were flooding, had a stuck float. took it off then checked all parts, ran perfect afterwards.
     
  5. CamaroMan79

    CamaroMan79 Veteran Member Lifetime Gold Member

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    Do you have a different carb you can try?
     
  6. Vince's79

    Vince's79 Member

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    After taking off the fuel bowl and metering block again and cleaning it out, it ran great for a few seconds until the fender cover fell into the radiator fan :(. No damage but unfortunately we had to turn the engine off. When we go to start it again it went to back to the bad idle. It is almost as if a piece of dirt got free from the carb and and then re lodged itself in there to make it run bad after the restart. I am going to get a carb kit tomorrow and completely tear down/clean the carb. This is also the only carb I can get a hold of so I can't test it with another one.
     
  7. Blown Camaro

    Blown Camaro American by birth, drag racer by choice

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    Start the car and unscrew the sight plug on the primary and secondary bowls one at a time. Does fuel pour out? If yes, you have found the problem. Remove the needle and seat and blow it out or better yet replace it if it feels "sticky" and the gaskets on either side of the nut. Reset float height and enjoy.
     
  8. Vince's79

    Vince's79 Member

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    I finally got it running right. I pulled the carb off and got a rebuild kit for it and completely disassembled and cleaned it with new gaskets. It runs great like it was before. Probably just some dirt lodged in there even though I have a fuel filter. Thanks guys
     
  9. CamaroMan79

    CamaroMan79 Veteran Member Lifetime Gold Member

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    Good thing it wasn't anything serious.
     

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