Sputtering and high idle, Please help.
 

Hello everyone, I'm new to the page, been lurking for awhile.

I have a 1986 Mazda RX7 N/A, only things done that i know of is P/S and A/C delete. K&N air filter setup. 10.2mm ignition cables.

I have been having sputtering and bucking problems as well as using extremely large amounts of gas when this problem happens. it only happens about 2-4 minutes out of a 20-45 minute drive. the longer i drive the more it acts up. when it acts up there are also lots of backfires.

It idles at 1k when freshly warm, then jumps to 1500 after driving for about 5-10 mins, sometimes goes back to 1k but not always. also trys to die when at a red-light while its sputtering.

The fuel filter was replaced 6-10 months ago. and within this month the TPS, Fuel pump, Coils have all been replaced. the TPS has been adjusted to .99 ohms. i had fuel injectors serviced 3 months ago and they said they where clean and still good. what should i do? what could be my problem? i know i have a small vacuum leak but i do not know where its at and have not been able to find it. (though i do not know how to fully find a vacuum leak)

Thanks in advance guys! hope we can find the culprit!