单项选择题
A.early fuel injection timing
B.leaking valves
C.a continuously open scavenge air port
D.low cooling water temperature
单项选择题 Which of the listed problems can be a cause of low compression pressure in a diesel engine?（）
单项选择题 When an air started, four-stroke/cycle diesel engine is being cranked, the starting air is admitted to each cylinder during what would normally be the（）
单项选择题 Which of the general advantages listed does the electrical pyrometer have over the mechanical pyrometer?（）