Car shuts off @ cold start

after i let it sit overnight i find i have to let it run while revving the engine or it will cut off, or when i pull off too soon w/o letting it warm up, the brakes aren't good and it cuts off @ a stop sign or a red light... but once it warms up, it's fine.

wth is the problem?

what year and engine size?

It would be helpful to post the year, model and mileage of your Grand Prix so people can weigh in to help.

sorry about that.. 1994 GTP 3.4L

First things first, how long has it been since you tuned it up (plugs, wires, fuel filter, pcv, air filter, etc...)? Start there if it's been a while. The 3.4 DOHC had lower intake vacuum leak issues. When the engine is cold, everything is shrunk, and the problem will be worse. When the engine warms up and the metal expands, the problem will lessen, possibly even go away. Spray carb cleaner around the base of the intake, and if it causes the idle to change, you found your problem.