1989 sidekick misfire when cold or when under electrical load

[Jamestb]

I previously tested the map according to your test page and it tested good. I checked vacuum lines and have no leaks. I dont believe I have a leaking injector because I did the fuel pressure test and it held 40 psi for 5 min. I have also plugged the egr and retested with no change. I do not get a missfire when I hold throttle at 1k with my foot. I only get a missfire when I turn on lights, a/c or fan. It will happen regardless of whether the engine is cold or hot.

I am thinking of changing the caps in the ECU or maybe have the injector cleaned and tested.