i got a problem when my bronco II 1986 gets to 3-4000 rpm in every gear it cuts out and i replaced destributer, rotary button, plugs, plug wires and destributer cap what else can i check
Put a timing light on it. I got a hunch the electronic advance isn't working. Disconnect the spout connector, and check for timing advance. Then reconnected it and check again. When connected it should advance the timing significantly.
If the timing is not advancing, it could be the computer, and possibly the TFI module on the side of the dizzy. There is also a chance it could be your coil.
Did you set the base timing when you swapped out the dizzy?
you thank thats what it is you dont thank it is in the fuel line some people says that and it runs good when idellin just 3-4000 it wants to skip and stuter ill check that
Well it certainly could be a fuel problem, and I'm not ruling that out. Checking if the timing is advancing or not is the place place to start as it's easy to check and rule out.
I think if it were a fuel problem it wouldn't run right at all, or would be more related to load and not RPM.
I'm with Noboby on the timing problem, thats probably it. But, as other possibilities in case its not a timing problem or TFI module problem, check the MAP sensor, the Throttle Position Sensor.