Diesel Engine Operations with Alternative Fuels presents the results of a study that analyzes selected parameters of the combustion process in a diesel engine when fueled with alternative fuels. It discusses the use of a unique test stand consisting of a motor vehicle with a diesel engine adapted to run on different fuels: liquid and gas. Intending to carry out the process of indicating the engine and measuring exhaust gas toxicity under near real conditions, the book demonstrates the implementation of a Worldwide harmonized Light vehicles Test Procedure (WLTP test). It shares research that seeks alternative fuels to power the diesel engine, including diesel and hydrogen, rapeseed oil with n-hexane and hydrogen, rapeseed oil with n-hexane, rapeseed oil and propane-butane gas, and rapeseed oil with n-hexane and propane-butane gas. The book will interest academic researchers and graduate students studying alternative fuels, vehicle operations, and engine operations.