sounds like the tran might be bad. mine did the same thing. I was like no problem I'll change the clucth. Get the trany out and nothing wrong with the clucth. So I truned the input shaft and get about five truns on it and it would lock up. Put a little a** on it and it would pop and spin freely for a little and do the same thing agian. So had to put a reman trany in. Never did find out what cased it to do that.

99 RS AEM Coldair intake
18x7 somethings
Phantom Tach W/Shift Light
A/F gauge
Kenwood KVT-512
Boston Acustic 6.5 up front& Fosgate 6.5 in back Alpine AMP MRV-F302 Pionner XM satellite radio
NX wet 50 shoot