Polaris Sportsman 500 EFI Owner's Manual page 113

TROUBLESHOOTING
Engine Pings or Knocks
Possible Cause
Poor quality or low octane fuel
Incorrect ignition timing
Incorrect spark plug gap or heat range
Engine Runs Irregularly, Stalls or Misfires
Possible Weak Spark Cause
Fouled or defective spark plug
Worn or defective spark plug wires
Incorrect spark plug gap or heat range
Loose ignition connections
Water present in fuel
Low battery voltage
Kinked or plugged fuel vent line
Incorrect fuel
Clogged air filter
Reverse speed limiter malfunction
Electronic throttle control malfunction
Other mechanical failure
Possible Lean Fuel Mixture Cause
Low or contaminated fuel
Kinked or plugged fuel tank vent line
Low octane fuel
Clogged fuel filter
Possible Rich Fuel Mixture Cause
Fuel is very high octane
Stopping/starting without adequate warm-
up
Incorrect fuel
Clogged air filter
110
Solution
Replace with recommended fuel
See your Polaris dealer
Set gap to specs or replace plug
Solution
Inspect, clean and/or replace spark plug
See your Polaris dealer
Set gap to specs or replace plug
Check all connections and tighten
Replace with new fuel
Recharge battery to 12.5 VDC
Inspect and replace
Replace with recommended fuel
Inspect and clean or replace
See your Polaris dealer
See your Polaris dealer
See your Polaris dealer
Solution
Add or change fuel, clean the fuel system
Inspect and replace
Replace with recommended fuel
Replace filter
Solution
Replace with lower octane fuel
Allow engine to warm up before operat-
ing and/or stopping
Replace with recommended fuel
Inspect and clean or replace