4.16
ELECTRONIC FUEL INJECTION
9923523 - 2012
RANGER
RZR 570 Service Manual
© Copyright 2011 Polaris Sales Inc.
Fuel Injector Troubleshooting
Injector pr oblems typically fall into th
ree g eneral
categories- electrical, d irty / clogg ed, or leakage. An
electrical pr oblem u sually causes o ne o r b oth of the
injectors to sto p fu nctioning. Several methods may be
used to check if the injectors are operating.
• With the engine running at idle, feel for operational
vibration, indicating that they are opening and
closing.
• When temperatures prohibit touching, listen for a
buzzing or clicking sound with a screwdriver or
mechanic's stethoscope.
• Disconnect the electrical connector from an
injector and listen for a change in idle performance
(only running on one cylinder) or a change in
injector noise or vibration.
NOTE: Do not apply vo ltage d irectly t o t he fuel
injector. Excessive voltage will burn out the injector.
Do not gro und the inject or with t he ignition o n.
lnjector(s) will open/turn on if relay is energized.
If an injector is not operating, it can indicate either a bad
injector, or a wiring/electrical connection problem. Check
as follows:
Injector leakage is very unlikely, but in rare instances it can
be internal (past the tip of th e valve needle), or external
(weeping around the injector body). The loss of system
pressure from the leakage can cause hot restart problems
and longer cranking times.
Injector problems due to dirt or clogging are unlikely due
to the design of the injectors, the high fuel pressure, the
use of filters and the detergent additives in the gasoline.
Symptoms that could be caused by dirty/clogged injectors
include rough idle, hesitation/stumble during acceleration,
or triggering of fault codes related to fuel delivery. Injector
clogging is usually caused by a buildup of deposits on the
director plate, restricting the flow of fuel, resulting in a poor
spray p attern. Some contributing fact ors t o injector
clogging includ e; dir ty a ir filters, hig her than nor mal
operating t emperatures, sh ort o perating intervals an d
dirty, incorrect, or poor quality fuel. Cleaning of clogg ed
injectors is n ot recommended; they should be replaced.
Additives an d hig her gr ades o f fuel can be used as a
preventative measure if clogging has been a problem.
Fuel Injector Test
The fuel injector is non-serviceable. If diagnosis indicates
a problem with the injector, test the resistance of the fuel
injector by measuring between the two pin terminals:
Fuel Injector Resistance Specification:
11.4 - 12.6 Ohms
Disconnect
and test here
Air Box
Summary of Contents for 2012 RANGER RZR 570
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