I'm really at a loss on this one. 87 IROC, 350 TPI, trying to get it to idle smooth. It's comfortable idling only around 1500 RPM or so, and it revs up and down a few hundred RPM. (It will die if I try to turn the set screw to get it down around the recommended 700-800.) It starts to die down, then revs to catch itself before dying. Also, it has a pretty good miss going as well. The really wierd thing? I unplug the electronic advance wire (the brown wire connector on the passenger's side wire harness) and it smooths out considerably. The miss is still there though. But it seems to idle way better. I did try pulling wires off the distributer while it's running, and pulling a couple of them causes no change. I've looked at the plug wires a hundred times to make sure two aren't switched, and they're fine. All injectors are clicking and ohms check good. I just did a new IAC, I'd done cap and rotor, plugs, fuel press regulator, plugged a bunch of vacuum leaks, checked TPS voltage, new O2 sensor, removed and cleaned entire plenum/throttlebody out, checked base timing...no idea what the deal could be. About the only thing left is wires, but that wouldn't explain the smoothing out when I disconnect the computer from the advance. Any ideas? Thankyou in advance!