tps problem?

[c.boots]

ok i need help:wavey:, i have a bone stock 93' 240sx coupe with ka24de which has been converted to 5-speed and im having issues with my cars rpms dropping whenever i come to a stop or go into neutral. i've had this problem before and swapped out the iacv with a new oem one, this took care of the problem for about a month and now its back. i've been looking in the fsm and found out that automatic trans 240s use different throttle position sensors than the manual versions. the auto t.p.s. has a " hard closed position switch" which i dont know what it does exactly, the manual versions dont have this switch. my questions are " what does this switch do?", " would having this switch be causing my idle to drop?" and " should i swap it out for the manual one?". tomorrow im going to be checking the tps with a volt meter to see if its good along with the vacuum lines, grounds and maf.

hope you fellow zilvians can help cause im still kinda of a noob when it comes to this engine stuff.:bowrofl: