What to Do If Your Generator Makes a Popping Noise in St. Louis

If your generator makes a popping noise, immediately switch it off, let it cool down, check the fuel level and quality, inspect the air filter and intake for blockages, examine the spark plug and ignition system, and look for exhaust restrictions. If the noise continues or you’re uncomfortable checking these parts, call a trained technician.

Licensed to serve residential & commercial clients in St Louis and Nashville.

 

Immediate Steps to Take

 

• Turn off the generator and disconnect any electrical loads.
• Allow the engine to cool for at least 15–20 minutes to avoid burns.
• Move the generator to a well-ventilated area if it’s running indoors or in a tight space.

 

Why Generators Pop

 

Popping noises can stem from uneven combustion or backfiring inside the engine or exhaust system. Common causes include:

• Dirty or clogged air filter preventing the correct air‐fuel mix
• Old, contaminated, or low fuel leading to misfires
• Faulty spark plug or ignition timing issues
• Exhaust blockages or damaged muffler

 

Checking the Fuel Supply

 

• Ensure there’s enough fuel in the tank and it’s fresh. Gas older than 30 days can degrade and cause engine knocking or popping.
• Look for water or debris in the fuel tank. Drain and clean the tank if you find contamination.
• Use the correct fuel/octane rating as specified in your owner’s manual.

 

Inspecting the Air Filter and Intake

 

• Locate the air filter—usually behind a cover on the side of the engine.
• Remove the filter and hold it up to bright light. If you can’t see light through it, it’s clogged and needs cleaning or replacing.
• Clean a foam filter with warm soapy water, let it dry, then re-oil lightly. Replace paper filters if dirty.

 

Examining Spark Plug and Ignition

 

• Disconnect the spark plug wire and remove the spark plug with a socket wrench.
• Check the gap between the plug’s center electrode and ground electrode with a feeler gauge; adjust to the manufacturer’s specification.
• Inspect for heavy carbon deposits, oil fouling, or damage—replace the spark plug if necessary.
• Ensure the plug wire is securely reattached and there are no cracks in the insulation.

 

Assessing Exhaust and Muffler

 

• Look under the generator for any dents, holes, or rust in the muffler or exhaust pipe that can cause backpressure.
• Tap gently on the exhaust system—loose baffles inside will rattle or pop under load.
• If you suspect blockages, carefully remove the muffler cover and clear any debris or soot buildup.

 

When to Call a Professional

 

• If you’ve followed all inspection steps and the popping noise persists.
• If you detect fuel leaks, strong exhaust odors, or see visible engine smoke.
• If you’re not comfortable performing mechanical checks—generators contain hot parts and high-voltage components.
• Ask a certified technician to perform a full tune-up, including carburetor cleaning or fuel system service, to restore smooth operation.