Subtle Jerking/Surging when cruising between 2-3krpm?! Help!

[Bobby12many]

I just purchased a 92 DOHC and have noticed a slight amount of stumble/surging when cruising at a constant speed between 2k and 3k rpm.... It also seems to affect my ability to start solidly and smoothly, but shifting above 3k and revmatching is smooth as butter.

My idle also has an intermittent fluctuation but holds between 500 and 1000RPM. I originally suspected this as an AIV related problem, and pulled and plugged the whole system today. My car seems to have gained some low end grunt from removing the AIV, but the other problems are still there..... Any ideas?

[Soy]

I had similar problems with my car - did the same thing by yanking the AIV. Problems persisted, so I ran some seafoam through the gas and oil, then changed the oil, filter, and fuel filter. Everything seems to have cleared up on mine now.

So what I'm saying is check your fuel filter, and maybe run some seafoam through the fluids.

James