Aren't air/fuel ratio gauges on fuel injected engines pointless? Doesn't the computer read and evaluate the correct reading so many times per second or something like that? I tried one of those and it just threw readings all over the place. I think I hear of something like long-wave gauges or something like that that are meant for f/i engines? I dunno.
I got a volt meter for my 3rd gauge. I like it. Was a good indicator when my alternator starting going.