单项选择题
A.up and draw in a fresh air charge B.down to burn off fuel C.down to compress the fuel air charge D.up and force out the exhaust gases
A fuel injection valve opening at pressure lower than n...
单项选择题A fuel injection valve opening at pressure lower than normal will result in（）.
A.late fuel injection B.early fuel injection C.high exhaust temperature from that cylinder D.decreased effective stroke from that injector
In a diesel engine, exhaust valves open before the inta...
In a diesel engine, exhaust valves open before the intake ports are uncovered to （） Ⅰ.reduce pumping losses Ⅱ.reduce back pressure
A.Ⅰonly B.Ⅱonly C.bothⅠand Ⅱ D.neitherⅠnor Ⅱ
Which of the engine components listed increases air cha...
单项选择题Which of the engine components listed increases air charge density and helps to improve engine operating efficiency?（）
A.Intake manifold B.Water-cooled exhaust system C.After-cooler D.Exhaust diffuser
