Diesel engine with a combustor which provides combustion products to reduce NOx production in a combustion chamber

A method of operating a diesel engine assembly having a combustion chamber is disclosed. The method includes the step of determining a desired level of NOx for exhaust gases exiting the combustion chamber and generating a fuel control signal in response thereto. The method further includes the steps of injecting an amount of combustor fuel into a combustor based on the fuel control signal and combusting the amount of combustor fuel in the combustor so as to produce combustion products. The method yet further includes the steps of advancing the combustion products into the combustion chamber during an intake stoke of the diesel engine and injecting diesel fuel with a fuel injector into the combustion chamber while the combustion products are located in the combustion chamber during a compression stroke. The method still further includes the step of combusting a mixture of the diesel fuel and the combustion products so as to produce exhaust gases during a power stroke. An engine assembly is also disclosed.