Controller shows E10 and the engine cranks but fails to fire; spark is weak or absent.

Safety first: Turn OFF the generator, disconnect the battery, and remove the spark plug cap before working near the flywheel or ignition components.

• Inspect spark plug: Remove the spark plug using the correct socket. Check for heavy carbon deposits, oil fouling, or cracked porcelain. Clean lightly with a wire brush or replace with a DuroStar‑specified plug gapped to the correct specification.
• Check spark strength: Reconnect the plug wire and ground the plug body to the engine block. Crank the engine and observe the spark; it should be strong and blue. If weak or absent, proceed to coil checks.
• Inspect ignition coil and wire: Examine the ignition coil and high‑tension lead for cracks, burns, or damage. Ensure the coil mounting bolts are tight and the air gap to the flywheel magnet is set per the manual. Replace the ignition coil assembly if defective.
• Check safety interlocks: Verify that any emergency stop switch or low oil shutdown circuit is not grounding the ignition unintentionally. Disconnect the kill wire from the coil and test for spark again; if spark returns, the issue is in the safety or control circuit.
• Control board check: If all ignition components test good but no spark is present with the kill wire connected, the control board's ignition driver may be faulty and require replacement by a technician.