Abstract: A system and method of controlling an engine includes sensing a concentration of NOx in exhaust gases produced by the engine and generating a sensed NOx value representative thereof, and controlling an engine control set point as a function of the sensed NOx value. The system also calculates a NOx difference value by subtracting a base NOx value from the sensed NOx value, and if an absolute value of the difference value exceeds a threshold, modifying the set point as a function of the NOx difference value. The method also includes sensing engine RPM, sensing engine manifold absolute pressure (MAP), determining the NOx value as a function of sensed engine RPM and MAP.

Abstract: A system and method of controlling an engine includes sensing a concentration of NOx in exhaust gases produced by the engine and generating a sensed NOx value representative thereof, and controlling an engine control set point as a function of the sensed NOx value. The system also calculates a NOx difference value by subtracting a base NOx value from the sensed NOx value, and if an absolute value of the difference value exceeds a threshold, modifying the set point as a function of the NOx difference value. The method also includes sensing engine RPM, sensing engine manifold absolute pressure (MAP), determining the NOx value as a function of sensed engine RPM and MAP.

Abstract: A heater for gas fuel mounted to a pressure reducing regulator to warm the gas after the temperature is reduced by the pressure reduction. The heater receives the fuel from the regulator through an external pipe and has separate gas and coolant passages therein. The coolant passage receives liquid engine coolant that heats both the gas and the regulator. A heater core has a plurality of radially extending fins around which the gas passes with the coolant passing through the interior of the core. Coolant flow is regulated by a thermostat that is responsive to the temperature of the gas to open and close the coolant passage.