Engine irregular when cold

1994 ALL OTHER MAKES ALL OTHER MODELS
80,000 MILES
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GAZY
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When the engine is cold, it starts ok but at idle it is irregular, shakes and seems to backfire. It turns at between 900 & 100 RPM. After 5 or 6 minutes, when it's warm, it stabilizes and works fine the rest of the time. Changed spark plugs because they were sooty and black. Changed fissured distributor cap and spark plug cables. Smoke at tailpipe is white. Still searching for the cause.
Oct 30, 2011 at 12:16 AM
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MERLIN2021
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Excessive white smoke is usually a blown head gasket or cracked head. Do a block test. Check steal seal.com for more info. In your case as it heats up it could be sealing the leak a bit.
Oct 30, 2011 at 4:41 AM
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GAZY
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Thanks Merlin, will check both gasket & head. Locally somebody said I should also check the Idle Control Valve, what do you think? There is also a strong gasoline smell in the exhaust smoke. Again, thanks.
Oct 30, 2011 at 6:37 PM
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MERLIN2021
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Idle air control if defective will cause sralling hot or cold. Do a compression test and also take vacuum readimgs, you may have a bad intake manifold gasket, that reseals when it expands during warm up.
Oct 31, 2011 at 8:16 PM
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GAZY
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Thanks again, will do. Cheers.
Oct 31, 2011 at 8:38 PM
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