Learn why small engines surge, sputter, stall, or run unevenly. Symptom‑based explanations for rough running conditions.
If your engine idles up and down (surging/hunting), the computer or governor is over‑correcting for an air‑fuel imbalance. These non‑invasive checks help identify the likely cause without repairs.
A mower that runs rough or surges is almost always dealing with carburetor blockage, stale fuel, vacuum leaks, or governor issues. This guide shows you how to fix each one.
A small engine that runs rough at every speed is dealing with fuel, air, ignition, or mechanical issues. This guide shows you how to diagnose and fix the problem step‑by‑step.
Small engines run rough when the carburetor is dirty, the spark plug is weak, fuel is stale, or airflow is restricted. This guide covers the top causes and how to diagnose each one.
An engine that idles unevenly is struggling to maintain a stable air‑fuel mixture. This guide covers the most common causes and how to fix them quickly.
An engine that stalls under load is being starved of fuel, spark, or airflow. This guide shows you the most common causes and how to fix them quickly.
An engine that sputters or coughs is struggling to maintain a clean air‑fuel burn. This guide covers the most common causes and how to fix them quickly.
If your engine revs up and down repeatedly, the cause is almost always a fuel restriction, carburetor blockage, or governor issue. This guide shows you how to fix it fast.