Posted this on another forum, but figured I'd share it here as well just in case any of you Na guys are having a similar problem.

So I've had this issue since I bought my '93 NA 2 years ago. Occasionally the car would hiccup when accelerating, I wouldn't classify it as a misfire since it was a one time deal, not a series of misses. Usually it would happen when the engine was still warming up and under partial throttle. Tune ups (plugs wires and air filter) would diminish the problem but it was still there. Once the engine was up to operating temperature the problem wouldn't occur.
So I was thinking maybe a TPS issue, or maybe oxygen sensor, but the car wasn't displaying any diagnostic codes. I was about to replaced both anyway since I was out of ideas when Hector at RSpeed suggested I replace the ecu temp sensor. This isn't the sensor for the gauge, but the one on the back of the cylinder head below the coil pack that the ecu looks at. It was a $35 sensor, and has seemingly fixed the issue! Figured it might help a fellow enthusiast who might be having the same issue.