Yeah they are inaccurate, but unless you can afford to buy a wideband, it is better than not having one... I have one in my car and find it works ok for street tuning just to make sure im keepin it in the green... Im going to ditch it for a wideband eventually but for now i like it just because i can get some kind of idea to where i am at to keep from blowing my shit up...


by the way....
red = switched power
black = ground
purple = O2 signal (white wire on O2 sensor)