Allright, I'm just throwing this out there for all you puzzle solvers. I bought an '87 GT about a year ago for $200.00. That gives a clue to the condition it was in. But it only had 80k on the odometer so I couldn't pass it up. A guy bought it for his son and he lost interest in it. Anyway, the car was in pieces. I've since put it back together, mostly. It had been sitting for about 3 years. I got the engine running but it seems to have a miss in one of the cylinders. I've checked fuel pressure and vacuum. Both those seem good. What I want to know is what kind of flowchart or step by step procedure is out there to determine the cause. My gut reaction is a clogged injector but I would like try to eliminate all other possibilities first. I don't want to just start replacing stuff at random.

Yes, very expensive to just start replacing stuff. Here is a link to the Fiero Service Manual:
http://spad.sytes.net/fiero/manuals/

Download the manual (76 megs) to your PC. Lots of good info including flowcharts.
Pontiac_Fiero_1986_Service_Manual.pdf

[This message has been edited by Hudini (edited 07-13-2007).]

Well that would be a great idea but..............I'm on dialup. I know, dark ages and all. Have issues with Comcast and can't get DSL in my area. Right now I could probably buy one off ebay and have it delivered before it downloaded. My chiltons is very little help.

How do the usual suspects look, the plugs, wires, dist cap, and rotor button?

The fuel injectors can definitely become clogged. I had a set from my junkyard engine sitting for about 2 years with fuel in the fuel rail. When I finally changed over the engine the injectors were all clogged. Rich at Cruzin Performance could only get 4 of the 6 flowing to spec again. (BTW- He refunded the money for the 2, very unexpected, good guy to work with, highly recommended)

You can take a timing light and place it on each plug wire and see if one wire shows the miss.

Yup, I ran down the electrical pretty easy. They're all getting fire. Recently my daughter's car had a miss, 3800 Buick. Two plugs were getting weak spark. Turned out to be the ignition module under the coilpack.
I'm thinking I should run a compression test next. That would rule out any sort of cylinder breach.

Sounds like you have it covered. I was going to suggest noid lights but they won't show a clogged injector. If you are getting a strong spark on all cylinders then you definitely have it narrowed down. The other issues are TPS where it wears down in one spot. You check that with a multimeter looking for smooth resistance through its full travel. A clogged fuel filter can also cause problems where the engine does not have enough flow at higher power settings causing a miss (more like bucking, lol).

Have you tried Winaldl yet? Its free software that allows your laptop to connect to the ALDL plug and read the engine sensors. Very useful. If you are interested you can build your own cable for about $10.
http://couleefiero.tripod.com/ALDL.htm
http://winaldl.joby.se/

Funny you should mention wialdl. Built myself a serial cable cause I thought it would come in handy one day. None of the computers in the house has a serial port !! Another thing to work on.