I finally finished my turbo/DIYPNP install on my 93. I noticed a few problems that are likely MS related. I started with the DIYPNP startup map.

1) First, the car idles right now around 13.5-14 afr according to my MTX-L. However when I blip the throttle, the wideband pegs at 22.3. It seems to run smoothly and there's no knocking so I'm assuming it's because I currently have no exhaust and the wideband is installed 2 inches from open air. I would think that it would have more trouble with idle since less air is flowing, but that seems to not be the case. Is that the most likely solution?

2) after running for 20-30 seconds I start hearing a buzzing at a constant frequency from around my IAC. I'm using the basic PWM settings from DIYPNP's startup map. I've read threads about IAC's buzzing, but I can't find a solid answer. I think the valve is working, as when I start it cold it idles high and then lowers as the engine warms up, but the buzzing worries me. Any ideas?

Thanks a lot!


[EDIT] nevermind. the wideband was mounted too closely to the air and i changed PWM frequency to 5*30.5hz and the buzzing is gone.