[88 Beater]

I did a little more trouble shooting and that positive battery cable may be more of a problem than I thought. I sort of assumed the voltage drop was happening in the ECM. However, my battery shows 12.6 volts with no load on it and I've only got 11.5 volts at the ECM fuse (with the fuse out and the key on). I know some other automotive electronics designed for 12-14 volts start to act weird when you get down around that 11.5 volt level and I bet it drops a little more when the ECM is pulling power.

I guess that shows it pays to start at the beginning and not assume things. I'll try to find a new battery cable on the way home from work tonight and see if that helps.