My 626 has been having an idle problem the past few months. Idles fine when the car is cold as it needs to warm up. Once the car reaches operating temperature upon stops the rpms go from 800 to 1700 and keeps going back and forth until take off. I think it may be the idle air control valve? If so i was wondering if someone could tell me the location of that part. Is it near the air intake? Any help would be appreciated.

 

Sorry for the late reply.
The idle air control valve is attached to the throttle body. Just taking it from the age of your car i would give the whole throttle body including the idle air control and EGR system a good cleaning.
I bet it could use new plugs, wires, cap and rotor as well.
Check the air intake hose for cracks.

Read the unofficial user's guide to the Mazda Protege. Your 626 is similar enough.