i'm having a problem with high idle on my quest

What is your question?

I believe my idle adjustment is sticking. When I let off the gas, the engine runs at about 1500 rpm and sometimes stays over 2000 rpm when i put it in park. doesn't do it all the time. not real sure what i need to do to fix it. there is what looks like a solenoid or a cam below the throttle body that seems to be sticking. what is that part called so I can replace it? any advice or help would be greatly appreciated.