So I have been having a weird problem with the idle of my car. When I let the car idle on its own, the rpms go up and down, up and down, like its trying to stabilize itself. Also when I drive my car and slow down to a stop, the car's rpm dips all the way down to zero and does the the idle fluctuation, but the idle dips go all the way down to until the car basically stalls itself. Can anyone help? I'm running a 1993 with a Begi Shanghai starter kit on band-aids (begi afpr, o2 clamp, greentop supra injector, and tweaked with the afm)

 

Adjust idle using bypass screw on the TB, on a warm engine with no electrical load, wheels straight and the IAC valve unplugged.
950 RPM is a good idle speed.

 

I had the same issue. on my car, it turned out that the ISCV was bad. I replaced that with one from a wrecked car and it idles fine now, even when cold.

However, i still have the second problem- it will die if occasionally. usually when I come out of boost and shift to neutral. so every time i come to a stop light, it dies. Could this be a problem with the throttle position sensor? does it not realize that I've closed the throttle until too late?