Hey, I put my AEM wideband in my 97 miata, in the spot on the header next to the cat, using the power from the stock O2 sensor wiring. Will having the 2nd stock O2 sensor plugged in post-cat affect my readings with the wideband, or anything? Thanks.

 

I don't believe Megasquirt reads or cares about the post cat O2 sensor, but I unplugged mine anyway. The plug is underneath the carpet under the rear of the driver's seat.