Controller shows E14 and the generator shuts down; exhaust appears unusually dark or engine runs roughly.

Safety first: Turn OFF the generator, disconnect the battery, and allow the engine to cool. Work in a well‑ventilated area away from open flames.

• Inspect air filter: Remove the air filter cover and element. If the filter is dirty or oil‑soaked, replace it with a DuroStar‑approved element. Do not run without a filter.
• Check fuel quality: Drain a small sample of fuel from the tank or fuel bowl into a clear container. Look for water, dirt, or phase separation. If contaminated, drain and refill with fresh fuel.
• Carburetor (gasoline): Inspect the carburetor for external leaks. If the engine runs rich (black smoke), the float or needle valve may be stuck. Lightly tap the carburetor bowl with a plastic handle to free a stuck float. For persistent issues, remove and clean or replace the carburetor.
• Injector (diesel): If misfiring or white smoke occurs, a faulty injector may be the cause. Use diesel injector cleaner in the fuel and, if no improvement, have a technician test and replace the injector.
• Fuel pressure (LP/NG): Verify that the gas regulator is delivering the correct pressure using a manometer. Incorrect pressure can cause lean misfire or rich running. Adjust or replace the DuroStar‑specified regulator as needed.
• Reset and test: Clear E14 and run the generator under light load to confirm stable operation.