92 integ, manual.

Once warmed up. My car shakes cuz of my idle goes up and down from 200-500 either when the fan goes on or when i turn on my lights.

I replaced the IACV. Still no difference.

 

check for vacuum leak

 

i dont' hear no hissing noise.

 

It's probably your FITV (fast idle thermo valve)located under the TB...take off the 3 10mm bolts, then the 2 8mm bolts that holds the plate on, then screw in the odd-looking white thing...take 2 flathead screwdrivers to do this...that acts as a vacuum leak, and probably your problem.