So I just installed a narrowband a/f on my car and it was working fine but I just took it out for a drive and its going from all the way lean to all the way rich in the matter of a second. When looking at the back of the gauge there is black (ground obviously) red (power duh) and a purple one (to 02 right?) So I cut into my 02 sensor and there were 5 wires no black or white ones but there was a purple one so DUH i thought it has to be that one. So I hooked it up at an idle and just tapping the gas it seemed to be working fine but now its going haywire. Whats up? thanks in advance-Tim

 

sounds normal.. it should bounce all over the place when normal driving as the car tries to keep the AFR at 14.7.. when you go WOT it should go deep into the green. Really NB gauges are pointless because they are only accurate around the 14.7 AFR when you are cruising and don't read WOT accurately.

 

just throw that guage away since all it's doing is jack ****. you need a wideband to actually tell you anything usefull. i like the ones with number read outs

dynotune sells the wideband and guage together