Air/Fuel Ratio problem

[SRraider]

What's up guys? I have a redtop SR in my 92 hatch 240sx. Ever since I got it running, I've had problems with the air/fuel ratio. When I start the car up (most of the time), my aem wideband is reading the a/f ratio between 14.7- 16.0 and as it warms up, it gets leaner and leaner until it doesn't even register. Thing is, while crusing the a/f is 13s and if i get on it, it will drop down to around 11-12 which is fine. Sometimes when I stop at a light, it will sit at 11-12 or just the opposite at 16-17. I got a SAFC II, hoping that would help level things out. Well, even with the SAFC, its doing the same thing. I had a friend suggest I replace my IACV(idler air control valve), which I did, but it runs the same. Another thing I noticed is that when its running and I unplug my iavc, it doesn't effect the way the car runs. On my friends redtop SR, when we pulled it, it killed his car. So I'm asking for help now. I don't know where to look next. I think it might be a problem with the harness, but I don't know where to look. Any ideas?

[xpicer]

use a multimeter an check continuity between the socket for the idle valve and the pins on the ecu socket .try looking for a ecu pin out