Just curious,
has anyone ever hooked up some sort of warning buzzer or at least a light or something, to their wideband, or egt gauge, to go off when your engine runs overly lean??

**** happens even when you're properly tuned ,
I was thinking that would be a lifesaver..

 

No, it would be too much work. You'd have to find a voltage resistance activated switch, but I don't think anyone makes one, so you'd probably have to fab one up yourself.

 

cant be THAT hard

there any aftermarket products that might able to help pull it off?
like vafc'ish products?
or standalone ecu's.. ?

 

Lean condition is set above 14.7 air/fuel ratio, but most people don't tune for a 14.7 stoichiometric ratio, so the device you use would have to have lean set at whatever air fuel the user chooses and everyone would choose a different setting.

We'll take 14.7 as an example, if you wanted the buzzer or whatever to go off at 15:1 AFR, you'd have to figure out how much voltage your O2 sensor is putting out at 15:1 AFR, then find some device to activate a switch at the point your O2 sensor reaches that certain voltage range.

To make things even more complicated, O2 sensors don't put out constant voltages, they bounce around from lean to rich all the time, so your buzzer would be goin off every 3 seconds at idle and cruising speeds.