I have an 86 rx7 na and I start it and the idle goes to 2500 goes down to about 1500 for about a minuet, then goes back up to about 2200 and stays there, could my idle air control valve going bad or what do y'all think.

 

Those fail shut. You're probably looking at sticky linkages or a thermowax problem. The thermowax is prone to getting clogged coolant passages.

 

Where is the thermal wax at?

 

Thermowax lies on the rear-facing side of the throttle body. It looks like a little plastic cylinder attached to your throttle plates.

 

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