'93 Regal GS Problem

I've got a '93 Regal Grand Sport, and it has developed a problem that has baffled my mechanic. In 3rd or 4th gear the car with lose power, and I can not excellerate until the car gives a "push," also before the push happens, the speedometer drops down as low as zero and jumps around and the rpms usually drop as well but I have seen them move up just slightly. I have already replaced the computer. Are there any suggestions what could be the problem???

Sounds Like The Sylinoid On The Tranny Causing The Gearing To Make The Engine Go Nutts.... Also Can B The Kick Down Cable On The Throttle Body... What Have U Done To The Car Lately Or Is It A Bone Stock Car That Just Developed This Problem... Tell Me And Ill Find Out Whats Wrong With It... My Dads A Transmision Specialist Sounds Like Thats Your Problem's Not The Engine....get Back to me

Its a bone stock car that just developed the problem. I have replaced the computer and thats pretty much it so far, my mechanic has been trying to see the car doing the "surging" or whatever the car does, but everytime i bring it to him, it doesnt do the problem. I did get someone who knows a little about cars to see the problem happen in action and he said he felt/sounded like the trans. was just barely slipping out of gear and then catching again. So it wouldn't surprise me if it is a trans problem.

yea sounds like tranny! not cheap but worth fixing.... mine only does that sumtimes but im not going to have it rebuilt... i had my oil flushed out and changed and it helped the problem....try that first if not spend 1200 and get it rebuilt its worth it