Hi. I've got a 1989 caprice, 305 FI, E engine code. My problem is this, when you take off from a start, the car will "hop" like you are stepping on and off the gas every half second. After you get going (above 10 or 15 mph) it is fine unless you floor it, then it does the same thing while accelerating.

When you first start the car, it is fine. It only seems to do this when it gets warmed up. It also does it a lot worse when it is above 80 degrees or so outside. You can also put it in neutral or park and the engine will do the same thing. Any ideas? I changed the plugs, wires, cap, rotor and coil. I thought maybe the coil was getting hot and causing this. Although it runs a lot better with more power, it didn't help the "hop"

Any ideas?

Also throwing a 32 and 34 code at me. I'm starting to think it could be a vacuum leak or a bad MAP sensor. Any help would be appreciated....