单选题When the normal compression ratio of a diesel engine is not very high, misfiring at light loads may be caused by （）Aoverloading the engineBlow exhaust valve liftCexcessive cylinder coolingDinsufficient mechanical clearance
单选题
When the normal compression ratio of a diesel engine is not very high, misfiring at light loads may be caused by （）
A
overloading the engine
B
low exhaust valve lift
C
excessive cylinder cooling
D
insufficient mechanical clearance
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