单项选择题
A.Ⅰonly
B.Ⅱ only
C.both Ⅰ and Ⅱ
D.neither Ⅰ nor Ⅱ
单项选择题 Forcing the exhaust gases form the cylinder of an operating diesel engine with the aid of a blower is known as ()
单项选择题 In a four-stroke/cycle diesel engine, badly worn intake valve guides can cause excessive().
单项选择题 Significant retardation of a diesel engine fuel injection timing will result in ()