1999 Ford Escort Jumpy Idling

When my zx2 is idling at 800 rpms, it feels like it is about to shut off. It steadily idles without the ac on. When the ac is on the rpms jump every few seconds as high as 2000. The same time the rpms jump a clicking sound occurs. The clicking is coming from the turning of the AC compressor. I was trying to take the compressor off and could not find the tensioner, and I loosened a bolt which caused some compressed fluid to leak for a moment but ended soon. I quickly put everything back in its rightful place. If you have some insight, I would really appreciate some advice.