Page 268 - Manual_Polaris_RZR_ProXP-20-21

EFI / FUEL SYSTEM

FUEL INJECTOR TROUBLESHOOTING FUEL INJECTOR TEST
Injector problems typically fall into three general NOTICE
categories- electrical, dirty / clogged, or leakage. An
electrical problem usually causes one or both of the Take note of PTO and MAG fuel injector harness
injectors to stop functioning. Several methods may be connectors before disconnecting them. The harness
used to check if the injectors are operating. lead to the PTO injector has green and blue wires and
the MAG injector has purple and blue wires.
• With the engine running at idle, feel for operational
vibration, indicating that they are opening and closing.
The fuel injectors are non-serviceable. If diagnosis
• When temperatures prohibit touching, listen for a indicates a problem with either injector, test the
buzzing or clicking sound with a screwdriver or resistance of the fuel injector(s) by measuring between
mechanic's stethoscope. the two pin terminals q & w.
• 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.
NOTICE
Do not apply voltage directly to the fuel injector(s).
Excessive voltage will burn out the injector(s). Do not
ground the injector(s) with the ignition on. 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 Fuel Injector Resistance Specification:
can be internal (past the tip of the valve needle), or 11.4 - 12.6 Ω
external (weeping around the injector body). The loss of
system pressure from the leakage can cause hot restart
problems and longer cranking times. IMPORTANT
Injector problems due to dirt or clogging are unlikely due Be sure to connect the PTO harness lead to the PTO
to the design of the injectors, the high fuel pressure, the injector and the MAG harness lead to the MAG injector
use of filters and the detergent additives in the gasoline. to ensure proper engine operation.
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 pattern. Some contributing
factors to injector clogging include; dirty air filters, higher
than normal operating temperatures, short operating
intervals and dirty, incorrect, or poor quality fuel.
Cleaning of clogged injectors is not recommended; they
should be replaced. Additives and higher grades of fuel
can be used as a preventative measure if clogging has
been a problem.

5.8 9930583 R01 - 2020-2021 RZR PRO XP / XP 4 Service Manual
© Copyright Polaris Industries Inc.