Kohler KDI 2504 Engine Misfires Under Light Load
Fault Codes & Symptoms
Engine runs rough or misfires under light load Related symptoms: - Engine stumble or hesitation - Intermittent drop in power Operator reports the engine feels like it has a miss when holding a steady, light load. The engine smooths out under heavy load and idles normally.
Confirmed cause: Intermittent short-to-ground on the #3 injector control wire within the main engine harness. The harness was rubbing against a bracket, and vibration at a specific RPM range caused the wire to contact ground, cutting out the injector. Repair performed: The damaged section of the engine wiring harness was repaired. The harness was re-secured with additional P-clamps to provide clearance from the bracket. Verification: The engine was brought to operating temperature and held at the specific light load and RPM where the misfire was previously present. The engine ran smoothly with no signs of a misfire. Technician notes: - This type of intermittent electrical issue can be difficult to diagnose because it often does not set a fault code. - Wiggle-testing the harness while the engine is running under the specific problem conditions can sometimes help pinpoint the location of the short. - The problem was not apparent at idle or high load, which made initial diagnosis challenging.