idling low

22re, it used to idle higher when i would turn the ac on, but recently it started idling lower when i turn the ac on. like 500 rpms like its fixing to die if i don't keep giving it gas. idles fine with the ac off ~800 rpms. i don't want to adjust the idle until it gets up to normal with the ac on, cause when i turn it off it would idle too high. is there a way to do this separately? what would be causing this problem?

Oh man I'll have to look this up again, Toyota's have a switch that makes the engine run at a higher RPM when the A/C is turned on so it doesn't cut off.