| 摘要 |
A fuel injection timing control system for diesel engines operating at high altitude, including a sensor for a parameter of the engine intake air, such as engine intake air pressure or turbocharger speed. This sensor communicates with a barometric pressure timing controller, and a throttle position sensor communicates with the barometric pressure timing controller. Nominal values of the engine intake air parameter at various throttle notch settings and various engine performance parameters are stored in a table, for a nominal barometric pressure. The barometric pressure timing controller determines the instantaneous barometric pressure by adjusting the nominal barometric pressure based on the difference between the instantaneous value for the engine intake air parameter and the nominal value for the engine intake air parameter, at the known throttle notch setting and the known engine performance parameters. The barometric pressure timing controller then adjusts fuel injection timing i n response to the thusly determined barometric pressure and the sensed throttle position, by advancing or retarding the fuel injection timing by predetermined values as the barometric pressure or the throttle position changes. The predetermined values of fuel injection timing are selected to reduce exhaust emissions and increase engine efficiency and performance under various barometric pressure conditions so that the engine may be operated continually and optimally under various barometric pressure conditions. |
