I recently purchased a 1988 V-6 Fiero GT V-6 and have replaced many parts; EGR, IACV, plugs, distributor cap, wires and the car starts a little hard (they dont like cold weather) The engine starts good now that it is a bit warmer but the idle will fluctuate/waver a hunderd or so RPM . So whats the problem Doc?
You might start your learning by using the search function and do "hunting idle" , bad idle, fixing idle etc. There are tons of posts that have idle. The main one you will find to be vacuum leaks but there are lots of other reasons. A good way to learn about your Fiero..