when i rev up to 3000 the rpm starts to jump up-n-down between 2500-4000, but when i let off the pedal the rpm becomes stable. i'm not getting any tps codes or any other check engine codes... and after 4000 it barely gets over 4500.

 

sounds like distributor/ignitor problems

 

check the plugs and wires the car might not be getting spark under load.

 

This happened to me when I forgot to tighten my dizzy after doing the timing.

 

there's two wires that come out of the top of the distributor... one is exposed...

i'll try my friend's distributor.