Quad 4 misses at 2000 RPM

[srb60]

I have a very odd problem.
It is a 98 Chev Malibu, Quad 4. When running between 1800 and 2200 RPM it occasionally misses, it is enough to jerk the entire car. Once the car down shifts, no miss. Also every now and then when you go to pull out in traffic the car will just die.

What I have done:
New fuel filter, new Plugs, new coils, checked ignition module, checked OBD-No computer codes, Fuel rail shows 55 psi, cleaned ignition cam sensor, new O2 sensor, checked cat. converter, new throtle pos. sensor.

Additional info. I was told that the alternator was hooked up backwards when a new one was installed. I didn't think that was possible anymore. Driving down the road I can hold the throttle in one place while I knock the trans into neutral and the engine doesn't seem to know what to do. Keep same rpm, slow down or speed up.

Any ideas, I really like the car.

Thanks

[bcopeland]

How about the ignition coils?

[srb60]

yes, I have replaced both coils.

[srb60]

Follow Up:
The car finally lost power the other day to the point that I had to have it towed home. After some testing I discovered that the 1 and 4 cylinders were not firing. After trial and error and replacing a few parts with no success it turned out to be the "Coil pack housing" This is equivalent to spark plug wires. I had tested the continuity with an ohm meter and it tested ok. The only thing I can gather is that there was an internal short that under high voltage the spark was not following its intended path. Runs great now.