well im having trouble starting my 2002 tahoe, it turns over but never starts, i havent ever had a problem before so what could this be? maybe the fuel pump?

 

Could be the fuel pump,or it could be the security system.Kinda like the security relearn yu have to do when yu swap pcm's.I would try the other key that yu got with it.Is security light flashing?Can yu hear the fuel pump prime yu turn the key to acc?

 

not exactly sure whats going on with it, i pulled the vaccum hose of the fuel pressure regulater and some fuel drained out and when i put it back on the truck starts fine

 

did you say fuel drained out of the vaccumn line when you pulled it off. if so the fuel pressure regulater is bad and needs to be replaced. the diaphram inside is leaking.

 

Yikes! When you replace that FPR, do an oil change as well.