Hight idle when AC on only

[oldskuz]

Well a new problem came up and was not like this when I got the car and cant seem to find any leaks and those that I have found were fixed before. The problem is that when I activate the AC the idle will shoot up to about 2k rpms and stay there. Before it would shoot up but not that much.

So select AC shoots to 2k, switch out of it and back to normal and will do this again and again if I continue to switch back and forth into AC and out. Other then that the idle is just fine and car is running good just this high idle when AC is on. Any ideas?

[zKars]

Look at the engine and find the vacumm accuation device that has a hook/arm that touches the throttle linkage. There is a way to adjust it mechancially so it doesn't push as far. Other option is that something changed the vacuum and it now pushes farther than it did before, or it got bumped by accident.

[oldskuz]

I discontented the line which goes to the fast idle unit (F) and while its disconnected I engaged the AC and ac blew cold with normal idle. Hooked back the line to the unit and engaged AC and of course idle jumped to about 2300rpms... Does this help give a better idea to the source?

[oldskuz]

Yup it ended up being that solenoid which needed to be adjusted. Just wouldn't assume that to be the cause as it was fine before. Hmm...

[zKars]

Good to hear you got that solved. Now you'll lay awake nights wondering what changed that caused it...

[oldskuz]

^No kidding... Already cant stop thinking what could of caused the issue or if Im just masking the real problem by adjusting the thing....

[Zed Head]

Check the hose from the solenoid to the actuator. Small vacuum leaks will cause an increase in idle speed.