In replaced my distributor assembly. the old shaft was marked I removed it and noted the position of the distributor rotor but only after I removed it. I forgot that it actually moves when its removed. I believe that I have placed it back in the correct position before removal based on the movement of the teeth on the distributor shaft. I'm going to try timing it tonight. 2 questions, is the position of the distributor rotor suppose to be facing to hit #1 spark plug first? does it matter? or does the position of the distributor shaft only matter when setting the timing?

The position of the rotor when you remove the distributor is arbitrary.....it could point in any direction, doesn't matter. This is why you note the direction it is pointing before you remove anything. At this point, you will need to rotate the engine to TDC and then install the distributor so the rotor points at cyl. #1 (since you have no idea where the rotor waspointing before you removed it).

thanks! yes that's what I read after I posted this. luckily I have a local fiero guru coming over to help me tomorrow

Any piston hits TDC 2 times... You want #1 at TDC with both valves Close.
If failed this then timing is 180° out.
Pull #1 plug and watch compression to find right TDC.

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(Jurassic Park)

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Ok so I reset to TDC. I was 180 off so I rerouted the spark plug wires. Got the timing dead on. But once I take out the code pin from A and B and the car is warm it idled between 800-1000 bouncing. Then I took it for a drive and have hesitation and bucking between 1000-2000 rpm. I took out the replacement o2 sensor and put the original back in. Was a little better but still have fun doing issue and hesitation. Do I need to relearn the Ecm? I hve no codes.

quote Originally posted by jjd2296: Do I need to relearn the Ecm? I hve no codes.

It re-learns after a long enough drive....maybe your trip was too short or too slow.

You might be right I’ll take it for a longer drive tomorrow fingers crossed

So I need to disconnect the battery first for a minute or so?

You indicate the timing was "dead on". Did you set it with a timing light at about 10* before pulling the ALDL jumper or just leave it at the TDC on the distributor? If not adjusted with a light, you're not advanced enough and you will get the bucking when accelerating, or at higher rpm's.

If you want to reset the ECM, no need to disconnect the battery. Just unplug the barrel connector located near the battery. Its lead comes off the C500.

Yes used a timing light it’s at 10 degrees. I’ll double check again before disconnecting it.

ECM resets IAC when drive >35mph.
Until it does so won't idle right and other issues.

setting timing may wipe ECM "learn" functions but most times many also pull battery power for working on the car and that will wipe ECM stored data and will need to reset IAC etc.

All fixed thanks all for comments. Turns out I had a little vacuum leak on one of the lines going to the Throttle body and I had to clean the idle control valve and reset it. Then slightly adjust the timing. Runs like a charm now better than before.