The car has been doing this for quite a while and I'm not sure what it's due to. At idle the car is usually fine and smooth, however every few minutes it will get very rough, the rpm's dont drop or go up. The steering wheel shakes a lot and the engine sound gets a little louder, but the revs stay the same. You can see the steering wheel vibrate and feel it. It's a 95 auto, has new plugs - 1 step colder coppper plugs gapped at .035, new fuel filter, cleaned TB, recently used seafoam to clean out IM (problem started long before that was used), knock sensor was changed over the summer too, always use 93 gas. The only things that I"m thinking is the EGR, I've had a CEL on that for the longest time and one for the O2 in the cat. Or the motor mounts hmmm. Any ideas?

 

could be a bad torque converter, or bad injectors.

 

Ah that reminds me, the fuel pressure regulator is bad ~ran too high of psi on the stock one and it broke, so idle fuel pressure is 42psi instead of 32-34, and max is 44psi, so it's running very rich in the low end.