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Old 04-05-2004, 04:30 PM
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Misfire

I have a 1970 nova with a 350 with an edelbrock intake, demon carb, hei ignition, mild cam. I went to start my car yesterday and it started running really bad. It was misfiring horribly. It has been running beautiful for the longest time. This is just out of the blue. I had to keep my foot on the gas to keep it from dying. I looked at the cap and rotor and they are good, tested all wires and they are good. I pulled the plugs to see what they looked like and all 8 have kind of a white fluffy look to them. Also, it smells like it is running a little rich now. What does all this mean? Why did this happen just all of a sudden? Any help is appreciated. Thank you.

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Old 04-05-2004, 05:03 PM
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First, I would suggest checking your timing...If the distributor has turned and retarded your base timing, you won't get a complete burn on the fuel in the cylinder, causing a little rich smell and the crappy running you have described...That will give you a good place to start and let us help you from there...
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Old 04-05-2004, 06:39 PM
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I checked my timing and it is set at 10 BTDC. So it is not retarded. I am now having a hard starting problem, extended crank, but I think I found out why. My secondary fuel bowl is way too high and fuel was leaking down when the motor was turned off. I lowered the fuel bowl and it runs a little better but still has a little misfire at idle, ok at cruising. I don't know how the fuel bowl got that high. I just set them last month I think and made sure they were perfect. Is it common for the fuel bowl levels to just raise up by themselves like that? I also changed all 8 spark plugs. Runs better but still not smooth. I don't know what is wrong.
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Old 04-05-2004, 09:34 PM
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fuel level

does it have an old brass float in it that now has a hole soit takes on fuel and sinks to the bottom letting the needle and seat open making the fuel level extremly high???? you probally over adjusted to compensate for it now the level is to low and that would explain the problem still being present??
Jesse
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Old 04-05-2004, 10:14 PM
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The carb is only about 6 months old, still pretty new. I went to drive it to the store and now I have to keep my foot on the gas just to keep it from dying. When it warms up it will idle on its own but still feels like it has a misfire.
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Old 04-05-2004, 10:22 PM
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Sounds like you may have developed a vacuum leak somewhere. Take a look at all the hoses and spray some carb cleaner around the carb base and the intake gaskets. If you get an rpm change, you have a leak.
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