Also, many guys don't realize, that most those solenoids will but "kick up" the idle by itself. With the AC on, you usually have to have the pedal down a ways, and when it idles down, the solenoid will hold the thing "up." Some solenoids may be stronger than others
Why someone doesn't make one that is actually strong enough to kick up the idle by itself boggles my mind. Ive searched and searched but can't find one yet.