What's up with my idle???
 

When I'm stopped at a light or something, my 87 Supra occasionally revvs a bit and the RPMs jump up a few clicks. It has only been happening for a couple of days, but the time that the RPMs were up went from a about half a second to about 10 seconds. The car jerks just a bit when it happens, and the car shakes just a bit (almost like sitting in a big rig, but very slight). Automatic transmission, never done this before. What's up?

how much is a few clicks? do you have ac? mine does that when im at idle and i have the heater set to defrost mode or air conditioning on .., the ac compressor will cycle on and off in defrost mode and the rpms will rise and fall.. but the vibration you describe sounds like you may need a tuneup and the load is just making it more noticable..??
no ac? does it do it all the time or just when it warm or cold?