hey i have a 97 mustang gt, and about 86% of the time when i do a cold start on it, i turn the key over it fires to about 1000rpm then starts to stutter and eventually dies unless i tap the gas pedal 7or8 times... doesnt do this when warm, and it started off just once in awhile and lately it just starts to happend more and more.. any suggestions? i have already replace plugs, wires, fuel filter, and got a new idler pully.