What causes the noise in a diesel engine?
What causes the noise in a diesel engine? There are two sound types that emerge from a diesel engine. Combustion noise is created by the compression ignition process which compresses the air fuel mixture of the gas which creates higher temperatures upon increased compression until combustion occurs. Why does my diesel engine make a high pitch Hiss? Also, as another poster first pointed out (DucatiKiller), there is sometimes a piston slap that make a audible sound but not always in newer engines. The high pitch hiss noise you hear from some diesels as they accelerate comes from the turbo charger...