Fuel or Air Problem

[Screaming_302]

Hello There I am New to this site so i say hello to everyone that love's mustangs just as mush as me ok here is my problem

I own a 1989 ford mustang hatchback 5.0 5 Speed it is pretty much a stock motor except for the headers that were put on it and the exaust witch i did not put on there i bought it like that it has an off road H Pipe 2.5 inch and it ends up with dynomax turbo tubes stock LX Chrome tips. It has a HO 302 fuelinjected motor the problem that i am having iswhen i start the car it is a little cold natured witch it shouldnt be because it is fuel injected also when i drive the car and it gets good and warm the car looses alot of horse power and runs like pure *** when i get to where i am going and shut the car off it will not start until it has cooled for about 10-15 minutes then it will start back up but it spits and sputters untill you open it up and then it runs fine this is a very aggravating problem and i would deely appreciate some help on this problem