Problems with 91 firebird. Acts hesitant at times

[3.1L/w.040bore]

hey everyone, I have a 91 firebird. A/t and is mpfi. Well couple days ago while driving my car stated acting if I had no gas(dieing) , but I did have gas half tank. When I wiould give it gas it would hesitate and start to die for like 3-4 sec, and than will continue on fine. But when I was not stepping on gas pedal car would be fine. It happens while in motion or at stop(very random). Just started to happen; occurs more frequently every time I am driving. It is really wierd never seen a car do this. I checked all my fluid levels and wires they are fine havent had time to check spark plugs or fuel injectors. Not sure what it could be. Wondering if it may be due to timeing not really certain. When in park idle is constant at 700 RPM, which is normal. Could it be due to bad gas? The Dash lights stay fine. Acts as if low on gas or air, real hesitant when trying to give gas at times, not every time. It did it this afternoon just as I got home from work, so I let it sit in Idle, and it bounced very little between 500RPM - 800Rpm. Engine was not shanking. ANy ideas would be a great help.

[bszopi]

Could be the fuel pump about to go out.

[tractorman]

yep, I'd check fuel pressure first

[Joseph Upson]

I agree with the fuel pump cause. When you check it note that the pressure rises to a point as the engine rpm is increased. If it doesn't replace the pump. I missed my failing pump by not catching that and drove the car (camaro) on nearly a 600 mile round trip, towing another car on the way back. The intermittent stumble got worse and finally got the attention it deserved when it nearly left me sitting broad side facing on coming traffic at an intersection, one of the sacariest moments in my life. The people driving towards me must have thought I was playing chicken because they didn't appear to be slowing down.

[3.1L/w.040bore]

Thanx for the suggestions. I was thinking it was my ECM goin out. How can I check the fuel pump.

[3.1L/w.040bore]

Is the fuel pump in the tank with the fuel filter. How much will I be expecting to spend for this fix.