1991 Accord LX Idle/Shift Problems

I have a 1991 Accord LX. Recently I noticed it didn't want to change gears byitself (automatic). But you could change manually. I realized that the transmission computer under the passenger foot rest has burnt up. So I replaced it. Now the only problem I have is at idle (park or neutral) the car revs from 1000 - 3000 rpm slowly (up and back down approx. 4sec.) when you first start the vehicle. If you shift to reverse or park it stops the reving but shifts very hard. If you stop at a red light it revs again but this time quicker (up and down in 1 sec). What can cause this. SOmeone told me the throttle control sensor is the cause of this. I don't know. HELP!!!!