On my 22RE, I have a really low idle when the AC is on. I noticed on my intake that there is a spring with a white plunger in it (sorry, no pics) and that's broken. I figured it has something to do with the idle speed while the AC is on. I realize w/o pics it may be difficult to diagnose this problem, but we'll try anyway.

 

Without pictures it is kind of hard to say, but if i remember correctly, on the side of your intake (the side with all the vacuum hoses on) about in the middle there should be a piece with about 4 vacuum lines attached to it, 2 small, 2 large, and on top of it should be a plastic screw w/ spring. It controlls the idle-up when the AC is turned on. If its broken then you'll need to get it replaced for your ac idle-up to work... hope this helps... I would take a picture of mine for you but its dark and raining outside. Best of luck!

Ok... Found a picture and circled the part. Your part color may vary...

 

That's it. The plunger inside the spring is broken. Wish I knew what this part was called, would make ordering the part easier.

Thanks.