Toyota Repair: idling, adjustment screw, electrical connector

Question
i have a 1992 tercel and it seems like it ildes to low when the a/c is on. when it ildes up and down is that normal

Answer
No it's not normal, the idle speed should increase when the a/c is turned on, there is an idle-up valve located on the firewall, it has two vacuum hoses connected to it and an electrical connector, there is an adjustment screw on the valve, try turning this adjuster to see if the idle speed can be raised if not this valve may need to be replaced.