Can anybody offer help with my Firebird?

[DevNull]

I have a 1990 Pontiac Firebird with an automatic 3.1L V6. I have noticed that I am having this situation occur more and more frequently. What happens is that when I try to accelerate too quickly or drive up a steep hill, the car refuses to accelerate and instead just begins shaking slightly. I can rarely go more than 35 as I watch other angry drivers pass me.
I have found that as long as I do not accelerate too quickly, I can drive the car fine. It isn't even noticeable at highway speeds. I dread every stop light I come to, especially those at the top of a hill.
I don't know if its related, but every now and then, when accelerating from a stop is will start to shutter like it always does, then simply turn off and leave me silently rolling. This only happens every once in a while but its frequency is also increasing.
I'm getting sick of driving like there's a glass of wine riding shotgun. Can anybody help me troubleshoot this?

 

[br549]

I would first suspect bad spark plug wires' then move on to a stopped up exhaust system (muffler or catalyst).

 

[Silverstang]

Done a tune up on this vehicle? Clean the throttle body? Change the Throttle position sensor? There is allot that could be done to remedy this problem.

 

[Oreif]

How does the engine rev in neutral? If it seems to accelerate slowly, It could be the catalytic converter is clogging up. The second thing to check is fuel pressure. With a dirty fuel filter, a weak fuel pump, or a bad fuel pressure regulator, as soon as you give it gas, the lower pressure will cause the stumbling you describe.