I've been battling with this air/fuel nitrous cutoff switch (disables nitrous if voltage of o2 sensor goes lean or rich) for a week and its not working out.......so I'm wondering what other safety device or guage should I replace it with? I've heard fuel pressure safety switches aren't very trustworthy and often dont even work - is this true? What about an electric fuel pressure guage - could I be able to watch it while spraying and if there is any sudden drop let off? or would it be to late and already have caused damage if it drops?

My a/f guage + cutoff switch was my only safety net......although I'm not even going over a 75 shot, I'm not sure I need one.

Or as a last chance, does anyone know why my a/f guage would be reading .3mV too high? (this is the only reason the guage isn't working out) - predator reads correct voltage at .920 and the guage reads 1.18 to 1.25 - I've tried many different things and can't get it to work.