The EGR valve reduces nitrogen oxide emissions by recirculating a portion of exhaust gases back into the engine intake manifold. Exhaust Gas Recirculation EGR Valves Automotive Fuels Systems for 1.9 130. This in turn will reduce air flows. Improve thermal efficiency by reducing heat accumulation in the intake manifold., Unlike the EGR Valves assembly, there are no internal restrictions on the power pipe. All these benefits combined, Exhaust gas dilutes the air-fuel mixture, reducing combustion intensity, resulting in smoother operation., Manufacturer: zeshibai