1989 GTA TPI Hard start Problem?? Help Please.

Hello to all. Maybe someone here has a clue what my car problem is. First of all, I would like to know on my 89 5.7 TPI motor - what controls the "cold starting"? I know the car does not have a cold start valve or "ninth injector", I know that was on the earlier TPI's. The problem I am having is - all of a sudden the car does not want to start when it sits over night or when it sits for a few hours. It will continuously crank and then finally barely start. If I spray throttle body cleaner in the throttle body, it will start up immediately. Once it is running, the car runs absolutely perfect - there is nothing wrong with it. If I shut it off and go to start it back up - it starts right up. Even an hour later it will start right up. Fuel filter is fairly new, cap and rotor are new, wires and plugs are fairly new, air filter is fairly new. Initially, I thought I had flooded the car out and I messed with my Holley Adjustable Fuel Regulator (I tried everything up and down). But that is not it. The fuel pump is working because I do hear it come on. Does anyone have a clue what it could possibly be? I do not think it is the injectors since the car runs perfect once it is running. I do not see any leaks or smell any leaks. Are there any sensor, etc. that would control the cold start? Could it possible be a Mass AirFlow Sensor? Also, when I shut the car off, whatever the fuel gauge reads, the next day or a few hours later, the gauge is on zero. Should the system hold pressure? Sorry for the long-winder, I just wanted to explain it exactly. Thanks for your help! Later Mike ______________ =A0=A0 =A0=A0=A0=A0=A0=A0