i have some question about tunning the car using safc and a/f ratio guagge

- how can i test that during the car stop and the gear is normal ?
-OR during the car move ?
-AND if move at which gear can i do that ?

and any advice at doing that will be thanks alo

am i asked wrong question !!!!

my question in other way

if i have SAFC2 and have A/F guagge how can i tune my self ?