单项选择题
A.a leaking fuel injector nozzle
B.a clogged air filter
C.excessively early fuel injection
D.malfunctioning valves
单项选择题 Which of the following statements is correct for the design and installation of diesel engine cooling water systems?（）
单项选择题 High exhaust back pressure will result in an increase in （）
单项选择题 An increased differential between the inlet and outlet of a strainer usually indicates the strainer is （）