Hello, From air/fuel sensor you can measure -0.36 mA current at air -fuel ratio 13 ,0 mA at fuel-air ratio 14.7, ,0.36 mA at fuel-air ratio 17.7.This current is pumped by ECU in sensor circuit to keep voltage at 0.4 v between AF+ and AF-,better use a scan tool to read air/fuel ratio,even with K2 cla...