2000 Pontiac Grand Prix car stalls and backfires when cold

2000 PONTIAC GRAND PRIX
185,000 MILES • 6 CYL • FWD • AUTOMATIC
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DALTONZETT
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I have a 00 grand prix with a supercharged 3.8l. After the car completely cools down and the outside temperature is below 55-60 degrees car will run when first started for about 30 seconds then backfire and die. after that it can be restarted only if I put my foot on the gas pedal and if I don't keep it above 3000 rpms it just dies again. If I keep my foot on the gas it will stay running, but backfires and seems to miss. Once warm there are no signs of any problem. I have changed plugs and fuel filter. I got a flashing ses light once, but it just went away. Other than that it won't throw a code.
May 10, 2010 at 4:52 PM
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MMPRINCE4000
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It sounds to me like a convertor problem (partially clogged).

When you start it in cold do you get any smoke out exhaust?
May 12, 2010 at 9:49 AM