starter excite wire carrying stray voltage

[growler]

How do, i have a 93 ranger 4.0 that is running rough mostly at low speeds and idle, but also intermittently at other times and speeds. While checking electrical system for shorts i unplugged the starter excite wire form the starter relay and noticed that the idle improved slightly. checked it with a meter and when the key is in the run postion it is still carrying 5 volts. also, when the engine is running and the excite wire is removed from the relay, the idle improves and i can unplug the idle air control and the engine idle does not fall off. ANY HELP WOULD BE GREATLY APPRECIATED!

 

[Opera House]

Which starter wire on the relay has 5V?

 

[growler]

the trigger wire from the ignition switch, which goes too twelve volts when you move the key to the start position too trigger the relay.