单选题As the plunger moves up, the ports are closed and the fuel （） and delivered to the injector nozzle at very high pressure.Abeing compressedBto be pumped upCis pressurizedDare built up
单选题
As the plunger moves up, the ports are closed and the fuel （） and delivered to the injector nozzle at very high pressure.
A
being compressed
B
to be pumped up
C
is pressurized
D
are built up
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相关考题：
The plunger in a jerk pump is rotated until the release port is uncovered If the port remains uncovered all of the time, which of the listed operations will occur?A.No fuel will be deliveredB.The maximum effective stroke will be attainedC.The fuel delivered to the cylinder will be excessiveD.The injection nozzle will overheat and carbonize
As the plunger moves upwards in the barrel, injection will commence once the plunger bas_______the spill ports and the pressure builds up.A.opened upB.closed offC.lined upD.taken off
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