My bad its called "Right ignition coil" The same thing happened to me at 1500-2000 rpms. Started off very mild an progressively got worse. When I unplugged the MAF the car ran fine. I changed the right ignition coil and problem solved. If the car runs rich, my guess would be the ignition coil. I had a 3,000 rmp hiccup and that turned out to be a damaged crank position sensor wire (coming off the right distributor).

 

any updates on this thread? Anyone find out if their crank position sensor wire was damaged?
or isn't it the cam sensor wire you're talking about sc400CTI?