Construction & working of the various Aftertreatment technologies in Automotive/Automobile Engines Latest emission norms world wide for Automotive/Automobile Engines Various types of substrates for the Three way catalytic convertorWorking of diesel oxidation catalyst and various chemical reactions Selective catalystic convertorLean NOx trapDiesel particulate filter /Diesel particulate Trap and different configurations Lambda Sensor workingGasoline particulate Filter in Gasoline Direct Injection Author Introduction