Seriously, borrow a good ECU from someone and try that first. if you're doing a swap, it's more likely you have a wiring problem, so try to eliminate that first by using a known-good ECU. If you have no spark on #4, start checking from the plug back. Get a multimeter and do a continuity check on the plug wire, and go from there. Chances are it's something simple. If you're not sure if it's the plug wire, they're probably old enough to need replacing anyway.. I'm not telling you to take the shotgun approach to testing, I'm just saying there are many more things that it could be besides the ECU, and because the ECU is the hardest to test, do that last.

Better yet, try your ECU in someone else's car and see if their car runs like shit.. you have to establish some reference point to start from...