My 93 Z has 127,XXX miles on it. Original trans. I've got a really strange problem with it right now, and I can't figure out what it is. Here's a very specific description of it, hopefully to help the diagnosis.

It occurs at a low RPMs under light acceleration only. Somwhere between 1000 and 2000 RPMs. While accelerating, the car has has a hesitation and the RPMS jump up and down a lot, between 1000 and 2000. It seems to happen when it's cold, but not always. It only happens in 2nd and 3rd gear. On my drive home from work, it always happens in the same spots. At this one stoplight, I'll take a right hand turn at around 20mph and the car stays in 3rd gear. The RPMs remain really low(~1000) and the car almost acts like it's going to stall. Almost like a manual tranny would if you give it too much clutch and not enough gas. Under hard acceleration there are no problems. Any ideas?

 

Well if it's about to stall then i'd say it's a fuel delivery problem. But you say it jumps up and down RPM wise? I don't know what could cause that but my car would hesitate then vibrate really badly right before my tranny gave out. Could be a little of both. Have you taken it to a shop to have them drive it or look at it?