Controller displays E15 and the generator shuts down with a strong exhaust smell.

Safety first: Turn OFF the generator, disconnect battery negative, and allow the exhaust system to cool completely. Work in a well-ventilated outdoor area.

• Inspect exhaust outlet: Check that the Firman generator exhaust pipe is not blocked by snow, ice, nests, or debris. Clear any obstructions.
• Check muffler and piping: Look for crushed sections of exhaust pipe or a collapsed muffler that could restrict flow. Replace damaged components.
• Inspect exhaust temperature sensor: Locate the sensor on or near the exhaust manifold. Check wiring and connector for heat damage. Replace the sensor if its resistance is out of specification.
• Check for excessive soot: Heavy black soot at the outlet may indicate rich running; address fuel/air issues as well.

After corrections, reconnect the battery, clear E15, and test run while monitoring for normal exhaust temperature. Persistent faults require professional evaluation of engine combustion and exhaust backpressure.