Sounds like the problem I was having with my 116 motor. My mechanic gave me two options. A new idle speed control module for $300 or a manual idle control valve for $25. I had spent plenty at the time on my car, so the $25 sounded pretty good. I took a while to tweak it out to a good balance between air conditioning on in drive versus a/c off in park, but it is fine. I have read that the solder joints on the circuit board can cause the problem I have resoldered all of the joints, but haven't reinstalled the module yet to see if that did it. Thankfully, I remembered to ask my mechanic for the electric idle control valve back before I left.