1989 sidekick misfire when cold or when under electrical load

[fixkick]

warning, some of these cars, the 2 wire injector, signals failed, on the ECU, 2 wires, so the owner , (or shorted and blew up the ECU driver to it) and then he hot wires the j
at near the injector and or the ECU same 2 wires, at ECU, just look carefully both ends (visual inspected)

red and yellow pair