I just installed an Auto Meter Air/Fuel ratio gauge. The thing rocks. But when I turn the lights on, it'll drop the reading 2 LEDs to the lean side. I assume the headlights are putting a big draw on the system, causing the change in reading... Is there anything I can do for this?

 

the air/fuel gauge reads a scale of 0.0 to 1.0 volts from the O2 sensor and has a refrence voltage of 5.0 volts, I don't think it would notice any change in voltage unless you dropped below the 5.0 volt range. more than likely you are seing the computer trying to compensate for the added load on the engine that the alt. is putting on trying to power the lights by varing the mixture.