I have a 88 RX7 TII TAE. I recently had the alternator replaced and ever since then my idle would fluctuate very bad. When it is sitting in neutral it would drop way down to 500 RPM's and sometimes would stall out. Sometime it would stall and then immediately start back up. I also noticed if my headlights are on and say the rear defroster, it would idle fine as soon as you turn one of them off it starts to fluctuate once again, kinda as if not enough power was being used. Any ideas of what may be the cause of this and how to go about and fix it?

 

try replacing your boost air sensor, I have an N/T that had that problem a while back and I lucked out buy pocketing 1 for a scrap yard and it solded my problem.

 

thanks but i fixed it a little bit back but havent been on for awhile turned out to be a loose connection of one of the map sensors