I seem to have had this problem a couple times in my 86.5 na. After a long highway cruise, i went to part at the fast food place, hot shutdown right after getting off the freeway. i eat for about 20 mins or so and come back out to start it up, as soon as it starts up the engine starts shakeing and idleing at >500 rpm like the idle is adjust wway low, but even when i gave it some throttle it felt like it was misfiring cause i saw my shifter shakeing and the car was shakeing, after i blipped it into 3k rpms a couple times and let go the rpms dropped to a normal level and seemed to stop misfiring. Do you guys have any idea what this is? It sounds like an ignition problem sort of, i changed the spark plugs recently with ngk's but i havent touched the cap/rotor/wires. Any idea what the problem could be?