check the plug wires to see if there is a mix up. Also pull the distributor out and see if any of the wires got damaged when it came loose. the wires are old know and might have split open and could be causing a miss. another thing to check is the plugs on the firewall that go to the distributor and injectors. these plugs could have corrosion in them so check that. test the coil too and make sure you dont have cheap plug wires on it. all the pros on here recommend NGK wires and plugs. I know you already checked the ecm, but if it has not been replaced before check it again. it might have just gone bad and is throwing you off. my 1990 did his with a bad ecm.