This document discusses a seminar report on performance and emission studies of a diesel engine coupled with a gasifier running in dual mode. The objectives of the study were to design and fabricate a downdraft gasifier to produce producer gas from wood chips and mustard oilcake, and use the gas as a secondary fuel in a single cylinder diesel engine. Tests were conducted by introducing the producer gas partially into the engine's inlet manifold at varying loads to study the engine's performance and emissions. The document provides background on diesel engine operation, differences between diesel and gasoline engines, and the four-stroke operating cycle of diesel engines.