Polaris RANGER 500 2017, Руководство по обслуживанию

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9850043 R01 - 2017-2021 RANGER 500 / 570 Service Manual
© Copyright Polaris Inc.
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FUEL INJECTOR
FUEL INJECTOR OVERVIEW
The fuel injector is mounted into the cylinder head, with
the fuel rail retaining it from the top end. O-rings on both
ends of the injector prevent external fuel leaks and also
insulate the injectors from heat and vibration.
When the key switch is on, the fuel rail is pressurized,
and the EFI relay provides voltage to the injectors.
During engine operation, the ECU completes the ground
circuit, energizing the injectors. The valve needle in each
injector is opened electromagnetically, and the pressure
in the fuel rail forces fuel down through the inside. The
“director plate” at the tip of the injector contains a series
of calibrated openings which directs the fuel into the
intake port in a cone-shaped spray pattern.
The amount of fuel injected is controlled by the ECU and
determined by the length of time the valve needle is held
open, also referred to as the “injection duration” or “pulse
width”. It may vary in length depending on the speed and
load requirements of the engine.
FUEL INJECTOR TEST
The fuel injector is non-serviceable. If diagnosis indicates
a problem with the injector, test the resistance of the fuel
injector solenoid windings by measuring between the two
terminals
e
:
Fuel Injector Resistance Specification:
11.4 - 12.6 Ω
FUEL SYSTEM