I know this is not a chevelle problem but thought someone that worked on cars for a living may have run across this before. I have a daily driver work car, a 1994 Cavalier with the 2.2 4 cyl in it. My problem is at it's worst at 30 to 50 mph. The care starts to act as it is cutting out. Not really a misfire but like the fuel is being killed to it. It is not severely noticable but you can feel it going down the road, kind jerking. When you are in park, and rev up the engine, when you get to a certain point in the throttle you can start to feel it, like the motor is beeing choked, but you rev it up a little more and it comes out of it. I have replaced the fuel filter, plug wires and plugs (ac delco). Gas mileage is really bad too. Before I bought it it had just had a head gasket set put on it, and o2 sensor. Any ideas anyone???

are the fuel psi and volume corect. Im thinking fuel pump. Have you scanned it what are the baro readings,

I was also thinking fuel pump but it wouldnt normally cut out and then come back around again. Is the check engine light on?

I was also thinking fuel pump but it wouldnt normally cut out and then come back around again. Is the check engine light on?
I have seen them do that, I actually have a lab scope wave from saved and when it happened the pump rpm was surging with increased and decreased electrical load. I think it was getting hot from the high resistance and slowng down, then speeding up with power surges as it made good contact on some of the poles. But you are right it is not a very common thing.

IAC motor ? idle air control. try disconnecting the battery for a few minutes and reconnect and drive down the freeway for 20 minutes...............not around the block,