starts but stalls

i have a 1995 lumina with 3.4L DOHC. when the engine is cold it will start the rpm's go to 3000 and then it drops to like 500rpm and then sputters then dies. when the engine is warm it idels a little rough but never dies. i replaced the tps,iac,spark plugs and wires,and the injectors.:confused:

hi jeff, not real familure with 3.4 but would ck for vacuum hoses that are cracked/leaking.a little carb cleaner helps in finding a leak.Good Luck