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Backfire, black smoke

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Old Sep 12, 2010 | 08:15 PM
  #1  
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Default Backfire, black smoke

Hey guys,

Fairly n00b question. Today I was pulling out of my neighborhood under light throttle in 1st. At about 3krpm while still on throttle the exhaust let out a backfire that sounded like a whip crack and a huge cloud of black smoke. I've had this happen before and thought nothing of it. I could not feel anything in the driveline. I have the normal explosive backfire now and then letting off after a hard run, but not usually like this and now I'm just curious. Is this just from excess fuel sitting in the exhaust pipes?
Old Sep 13, 2010 | 02:46 PM
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sounds like it...
Old Sep 13, 2010 | 02:51 PM
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too much fuel.
Old Sep 13, 2010 | 02:57 PM
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9:1 is a good compression ratio, not an AFR.... :P
Old Sep 13, 2010 | 03:02 PM
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check for exessive fuel in your low/vacuum load cells. everything under 60-80kpa should be very low. When I had above 2 in those cells I would shoot flames all the time lol
Old Sep 13, 2010 | 03:03 PM
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My car does this too but I have severe ignition problems ATM. I like it when people duck, lol.
Old Sep 13, 2010 | 03:55 PM
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Wow, I have always had to wait until throttle lift to get farterfire. Please post your map. I want my car to do it while I have cruise control activated.
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