My Idle when I start the Car is fine.. around 850 - 900 RPMs..But after I let it warm up and take off, when I come to a Stop the Idle drops to around 150 rpms (almost dies out) and then up to around 750 and back down.. continues this until I start moving again then it runs fine.. But at a Stop it will do that, and sometimes upon start Up after car is warmed up.. but it does it cold as well if I just get in and go.. it will do that as well ... Anyone got any Ideas?

*Note: There is 53,000 miles on the Engine.. was rebuilt at 135K and car has 188k. I just changed out the Plugs.. The OG Owner I guess was running the Plugs that are LEADING in all 4 ports. Instead of the 9's for Trailing and the 7's for Leading... (read that in the FSM that was given to me with the Car.)

Oh and this, I have a 1990 Rx-7 13b GLX

 

Make sure your tps is adjusted properly.