About this gauge?
ZZ Performance

I like the fact that you can read all those paremeters and still add a sensor to read a/f ratio.
Also read and delete trouble codes is a nize feature.
I just ownder if its something you use to scan and then it has to como off the car.
Or can i leave it all the time to monitor the car.
Would it read true a/f ratio just like a wideband?