So my buddy hooked my air/fuel ratio gauge up and its not working, i think its because its one the wrong o2 which is it the dp or the up??? Please let me know

 

it should go on the down pipe. the up pipe is an egt, not an o2 sensor. plus it will not give the most accurate readings because its not wideband. i was a little bummed to hear this too, i have a A/F gauge also. it works, but it shouldn't be used to anything other than a broad idea of whats going on. thats what i use mine for.

 

really, ****ty but thanks that where he hooked it up at but i'll look at it maybe he screwed it up somewhere else, thnaks man.