... and inspect the density of NO and O2 via Electrochemical sensor so as to calculate excess air coefficient λ. The analyzer introduces ... , it also has optional equipments such as Induction Tachometer, temperature sensor, inner Micro Printer for customers to purchase. The newly-added ... SV-5Q full-automatic automobile exhaust gas analyzer SHENGWEI Tester Meter Detector 5gas CO,CO2, HC, O2, NOx