In this system, we will use molecular sieve to separate oxygen from the atmospheric air and this oxygen enriched air is supply to input manifold of the engine, which will improve combustion of the engine. Due to this we can reduce the emission of the NOx from the exhaust at the greater extent and avoid the problem cause due to presence of nitrogen in the engine. It will also help in reduce the size and help in increasing the efficiency of the engine. Due to the absence of nitrogen in the engine we will able to attain the higher temperature in engine and thereby increases power output. After separating the oxygen from air we will able to collect the nitrogen enriched air which can be used for various purposes.