85 jetta 1.8 idle control motor question

I have an 85 Jetta 1.8 gas and am trying to fix my rough idle problem. I think I have narrowed it down to the idle control motor. My question is when I unplug this motor while the car is running at idle, should anything different happen...stall, rev? Nothing different happens to the engine at all. Before I replace it, I wanted see if anyones know if this is normal. Also can I repair it?

Thanks in advance

Something different should happen when you disconnect. If your idle air control valve is stuck in one position causing an indifference, unplugging it will give you the same result. I understand your concern as this is a expensive part and nothing changes if replaced. Check all vacuum lines, spark plug/wires, o2 sensor, egr/gasket, air filter and distributor cap for wear. You could also clean your iacv with throttle body cleaner and see if releases some carbon. Good luck!

Thanks for the help, all the other engine components are new including timing belt. I am trying to set the timing and idle but is very difficult with a rough idle. The car accelerates/drives fine, just when it comes back to idle it is rough.

Im pretty sure its normal for nothing to happen if you unplug the connector to the Idle Control Valve/Motor. As far as I know, the Idle Control Motor goes to 'completely shut' once the engine is warmed up, and the idle speed is set with a set screw on the passenger end of the inlet/throttle body. (Unlike the fuel injection systems on most American cars). So you could disconnect the wires to the Idle Control Motor once the engine was warm - and it would not make any difference. I have a 90 Jetta, that came with the rubber tubes closed off, and not Idle Control Motor. Its starts just fine in warm weather - which is al it sees in far south Texas where we keep it.
For a rough idle, look of course for leaks in vacuum lines. I dont recall if your Jetta has hydraulic lifters, or mechanical adjustment lifters. If its mechanical adjustment, I would check and set them; and I like to use about .001" or .002" more valve 'clearance' than the factory specs call for. It may make a little more valve noise, but there is no chance you would ever burn a valve.
Could it be your idle speed is too low? That would make it rough. Again, you can adjust the idle speed on a MkII Jetta, though you cant on most of the fuel injected cars after 91. They probably make the idle adjustment tricky to get to though.