Have you tried to lube/clean all the return springs and wide open throttle then let fly closed several times
Make sure u have free play in the cable might put a little extra just till it idles correct.
Is the o2 sensor getting hot?
U could hook up three test lights to the outside (negative) side of the coils then to positive battery and watch to see if the the lights blink the same.
You could do the same with the injectors but u would have to have special probes to penetrate the wires.
Did u run compression check to make sure that the valve/ valves are not to tight?