That was a great explaination. Completely logical.
I did no disassemble the valve to clean it. I was trying to clean it through the valve openings.
I may do as you described and apply voltages to see if the valve has the ability to control the idle.
The valve looks like it is held together with a crimped band around the middle of it. I assumed it was not serviceable. I may just take it apart and try and clean it, since my next step it to purchase the valve anyway.
I appreciate your help.
1983' SL500 euro