I was just about to splice my signal wire when I came across a problem. I can't splice the o2 sensor because of type of wire. I need to splice the harness. Is it he white wire on the harness? That's my problem...(06 WRX JUST TO CLARIFY)
You REALLY don't want to do what you are about to... Search on here for narrow band, then return the gauge and buy a gauge that comes with a sensor.