94 Sputtering Problems over 50MPH Runs Rough, Hot

My 94 3800 Series I Motor runs rough in town and is worse when accelerating. Idles well. When driving in town, the temp gauge goes over the halfway point and that's when everything goes to hell. It will continue to drive good enough in town, although at stop lights it gets warmer, and it sputters while accelerating from them. When I get to the highway, the whole time I am accelerating it sputters, unless I put the pedal to the floor. For a while, when I leveled out at speed it would run fine, but now I have a really hard time getting the car to go over 50MPH. If I floor it and keep it there it might run 60. The temp gauge goes down on the highway, and sometimes that makes it run a bit better. I can't even think about turning on the air conditioner, because that makes every problem I'm having 2-3 times worse. Please help me!

You have an identical thread to this one, posted in the Olds 88 forum with good feedback!

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