I just bought a 91' 2.2 Cavalier off my buddy and took it to the shop to have it looked at. They fixed my ignition switch and said my exhaust needed repaired. I started it up with no problem and left the shop. I noticed it cuts in and out when I go up a hill lets say, but goes fine on level roadway. it kinda makes like a pop noise and wants to lose power if i give it gas when going up an incline. i noticed also it shakes a little bit when doing about 65 or over on the highway. what should i do at this point because i need the car to get back and forth to work...maybe a tuneup?

Check and see what the plugs look like, tuneup could do it. Do wires with it if you do.

Any check engine light? Check codes first, then unplug the map sensor and see if it runs better. Unless you have a scan tool and vacuum gauge and can actually compare the two, then do that :)

Also check fuel pressure.

It does sounds like your fuel pump or pressure is dropping it out. It sounds like you are getting fuel starved when under load and going up hills.

sounds to me it is a coil pack or plug wires i had the same car and it had the same problems went through lots of coil packs