单选题In the common rail system, excessive pressure in the header may be caused by （）Aimproper adjustment of the bypass valveBa dribble in the fuel injection nozzleCinsufficient leak-off through injection nozzle packingDa malfunctioning injection nozzle
单选题
In the common rail system, excessive pressure in the header may be caused by （）
A
improper adjustment of the bypass valve
B
a dribble in the fuel injection nozzle
C
insufficient leak-off through injection nozzle packing
D
a malfunctioning injection nozzle
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