I just installed an autometer a/f guage tonight and now I notice my car isn't idling normally (100-200 rpms). I didn't disconnect the batt, but it's acting as it does when the ecu is recalibrating itself. The guage seems to work fine, so does the a/f readout on my apexi TT, and the car runs as if nothing is wrong. I'm assuming one of my connections is bad (I'll check as soon as I have the time) but if that was the case and the ecu wasn't reading o2's couldn't I expect more then just a crappy idle? On a side note, is the guage, when its jumping all over the place, supposed to spend time with no lights on? I didn't expect it to ever just go black. Thanks.