单项选择题
All of the diesel engine cylinder firing pressures are normal, yet all of the exhaust temperatures are lowWhich of the following situations is responsible for this condition?（）
A.Excessively early injection timing B.Combustion knock C.Leaking piston rings D.Light load
单项选择题 Which statement about diesel engine combustion is true?（）
单项选择题 Diesel engine exhaust gas temperatures can be used to determine individual cylinder （）.
单项选择题 Improper cooling of a diesel engine cylinder liner due to the accumulation of scale deposits may cause （）.
