Engine Runs Irregularly, Stalls or Misfires

Content Source: 2021 RZR XP / XP4 1000 Owner’s Manual (9931524 R02) > Troubleshooting Chapter

IMPORTANT

The Owner's Manual for this vehicle contains warnings, instructions and other information you must read and fully understand before safely riding or performing maintenance on this vehicle.Always follow the warnings and instructions in Owner's Manual.

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Engine Runs Irregularly, Stalls or Misfires

Possible Cause	Solution
Loose, missing or kinked boost reference lines	Replace boost reference lines
Loose or missing intake system sensor connections	Inspect connections, tighten or replace as needed
Fouled or defective spark plugs	Inspect, clean and/or replace spark plugs
Worn or defective spark plug wires	Your POLARIS dealer or other qualified person can assist.
Incorrect spark plug gap or heat range	Set gap to specs or replace plugs
Loose ignition connections	Check all connections and tighten
Water present in fuel	Replace with new fuel
Low battery voltage	Recharge battery to 12.8 VDC
Kinked or plugged fuel tank vent line or filter	Inspect and replace
Incorrect fuel	Replace with recommended fuel
Clogged air filter	Inspect and replace
Clogged intake pre-filter	Inspect and clean (with soapy water) or replace
Other mechanical failure	Your POLARIS dealer or other qualified person can assist.
Possible Lean Fuel Cause	Solution

Low or contaminated fuel	Add or change fuel, clean the fuel system
Low octane fuel	Replace with recommended fuel
Clogged fuel filter	Your POLARIS dealer or other qualified person can assist.
Low fuel pressure	Your POLARIS dealer or other qualified person can assist.