s14 ka cuts out at idle

[Sc0ttyb0i]

i have a 1996 s14 with a ka24de. when i come to a stop it has trouble maintaining a smooth idle it fluctuates between 500-750 rpms without a/c. when i turn on the a/c it idles at about 1000 rpms and is fine, but if i turn the a/c back off it drops down to about 200 rpms and revs back up to about 600 and then cuts out. i dont know if it has a bad tps or idle regulator valve. has anyone else had this problem and does anyone know what it could be? I think i have a bad knock sensor and was wondering if that has anything to do with it.

Modified by Sc0ttyb0i at 12:23 PM 8/25/2009
Modified by Sc0ttyb0i at 10:18 AM 8/28/2009