Recirculation part of Exhaust Gas of Diesel engine into induction pipe (Fresh Air) slows the rate of flame propagation of engine. As a result, it controls max kindling temperature below regulation; thereby it prevents thermal dissociation of N2. When thermal dissociation of N2 occurs, N2 combines with Excess O2 of Exhaust Gas to NOx. As a result, it produces acid rain. EGR is the core technology of environment-friendly engine. It is very difficult to make EGR as a standard part of Module with this function. EGR has structure of 2-chamber and consists of a lot of geometric and precision tolerances.