Anyone want to guess how the hell that happened?
All I did was add a ground wire from my fuel pump to the trunk chasis. I went to start my car without looking at the afr, it ran for about a min when I noticed the gauge was completly black. Sweet! Now my sensor is trash, and possibly my gauge?

 

i've had a lot of trouble with those AEM widebands, especially if it is an older production one. if the gauge is completely black, verify that it is getting good voltage and good ground. normally when the sensor is messed up the display will still light up and it will read " - - -" I had the gauge itself fail on mine (sensor was ok). and AEM's tech support gave me a hard time when it came to returning it.

 

Yea, I dont see how the ground at the fuel pump could affect the wideband, but its the only work that was done before the gauge stopped working. The gauge has worked perfect for a couple thousand miles

BTW, should I cut the oem 18 gauge black wire, is it bad having two grounds connected?