
The lawn mower sound is typically due to a crack in the combustion system. A vehicle's combustion system features many components, such as cylinders, spark plugs, and exhaust, which are all susceptible to damage. These are the most common issues involving these parts:
Blown head gaskets can make your car sound like a lawn mower. In this case, note that a few other symptoms come along. For example, you might notice white smoke from the tailpipe, bubbling in the radiator and coolant reservoir, coolant loss, white-ish oil, and engine overheating.
Engine misfires can cause this issue. In such cases, it's common to notice chugging sounds, power loss, vibration, burning match-like smells, and excessive exhaust smoke. Also, the dashboard usually holds the check engine light on or flashing.
Usually, if it's an exhaust leak, you'll notice a noise that changes with engine speed. Also, watch out for fuel economy since this leak impacts it negatively. In addition, it's common to have the engine light pinging on the dashboard. Finally, exhaust fume smells can also indicate exhaust leaks.
A failing spark plug often causes this issue. In this case, the noise might even resemble chugging or banging. Usually, the symptoms that come along with this issue are fuel mileage loss, engine underperformance, lengthy starts, engine vibration, and rough idling.
A faulty wheel bearing can also cause humming or squealing sounds. In addition, keep your eye open for ABS failures, steering wheel vibration, and looseness, for they are satellite symptoms.
If this is the case, it's common to notice the noises changing as the engine cools down and again when it’s running at operating temp. You might also feel power loss, fuel economy loss, and exhaust fumes smell in the driver's compartment. Also, watch for your car's dashboard; the check engine light might be on for emissions-related failure. Finally, you might see missing bolts from the exhaust manifold or glowing red areas in dark engine compartments.
Explore the following typical inspection results that show a potential cause for the symptom and select the one you believe is similar to your vehicle's issue.

The technician already suspected the car's head gasket for the presence of whiteish milkshake-like oil. Then, after opening the vehicle's hood, he quickly saw signs of a blown head gasket.
During an underhood inspection, the mechanic saw black soot around specific areas, indicating a leak. Then, when testing the vehicle, the mechanic noticed the engine was overheating too quickly.
In addition, the inspection revealed that the noise was changing in rhythm according to the engine speed.
So, a blown head gasket can't do its central role, which is sealing the engine block and cylinder head. Therefore, a weak seal means leaking exhaust gas, coolant, and oil, affecting engine operation.

When doing an initial test, the mechanic noticed that the vehicle took too long to start. So, they checked the car’s underhood and spotted damages related to loose spark plugs—time for some repairs.
After running the engine, the mechanic noticed unusual sounds coming from the car's underhood. Then, they opened the hood and saw loose spark plugs "dancing" to the engine's vibrations.
The mechanic then did a closer inspection and noticed black soot around the spark plugs' area. They also noted some spark plugs close to being blown out of the cylinder’s head.
In addition, they saw boots and coils melting when inspecting the spark plugs. So the technician needs to do a replacement and re-test the plugs. In addition, they'll need to check the spark plug threads in the cylinder head to ensure that spark plugs tighten correctly.

The client brought this vehicle to the shop because of a loose steering wheel feel and a lawn mower sound. First, the mechanic lifted the car to do the underside part of the vehicle health inspection. Then, they noticed excessive movement in the Wheel Bearing & Hub Assembly. The shop needs to replace the faulty bearings.
Wheel bearings are critical parts that ease the vehicle's weight upon the wheel. Usually, mechanics inspect this system by lifting the car and checking how it behaves with no weight on the wheel bearings. In addition, damages in this part commonly result in noises, making it a significant suspect.
Damages in a wheel bearing cause the car to make odd sounds when moving; the sound changes with road speed regardless of the pavement type. Also, this type of damage can result in worn out tires quicker.

Apart from making lawn mower sounds, this vehicle also registered bad fuel mileage, power loss, and odd smells in the passenger compartment. The mechanic suspected a leak and lifted the car, spotting cracks on the exhaust manifold.
Manifold leaks affect the car’s exhaust system and produce a typical tailpipe emission smell. The exhaust leak smell comes from the cracked area whenever the noise occurs.
Typically mechanics spot this problem by lifting the car and checking its underside for black soot areas. In addition, it's common to notice missing or broken bolts in the exhaust manifold and other system flanges when inspecting this case type.
When the manifold cracks become more noticeable, they'll expand and contract according to the engine's heat, affecting sound waves. Hence, this type of motion results in odd sounds.

After lifting the vehicle to check under it, the technician quickly spotted a rust hole on the vehicle's muffler.
Usually, when searching for these leaks in a car, mechanics tend to look for black soot around the leaking areas. Hence, in this case, the mechanic saw this clue in the exhaust pipe.
In addition, while testing the engine, the mechanic noticed its noise changing as it warmed up; this happens because the engine's metal expands and contracts with temperature changes, affecting the size of the cracks and sound waves.
So, this motion of the exhaust system's cracks is why leaks in this area cause noise.
When further inspecting, the mechanic saw that a few spots on the exhaust system were missing the bolts. Plus, there were some rust holes.
Exhaust system leaks can develop into serious problems. So, the mechanic needs to assess this problem as quickly and safely as possible. In this case, they'll need to replace the muffler.

The client came into the shop complaining about a strange noise, power loss, and vibrations. The mechanic test-drove the car before the vehicle health inspection and noticed the dashboard’s check engine light flashing during acceleration. They also heard a lawnmower-like noise and felt chugging from the engine. They’ll need to do further testing to get to the exact cause.
When inspecting this vehicle, the mechanic noticed the "check engine" light flashing in the dashboard only while the engine made a lawn mower sound.
In addition, the car's engine was also vibrating and chugging after running for a while.
An engine misfire happens because the air that fuels the mixture in the cylinder gets compromised. It can also happen due to issues with the timing belt. This issue results in your engine jumping up and down.
That need Lawn Mower Noise significantly more often than average vehicle makes
The following chapters bases themselves on experiences from our auto repair shop; we'll describe related problems' causes and fixes.
Oxygen Sensor Replacement
Fuel injector replacement
Fuel pump replacement
Fuel filter replacement
Spark plug replacement
Ignition Coil Replacement
Exhaust manifold replacement
Mass air flow replacement
Air fuel ratio sensor replacement
Intake gaskets replacement
Exhaust manifold gasket replacement
Exhaust Pipe replacement
Intake air temp replacement
Spark plugs replacement
Spark plug wires replacement
Coils replacement
Computer Software update
Wiring harness repair or replacement
Computer replacement
Mass Air flow sensor replacement
Throttle body replacement
Throttle pedal replacement
Bank 1 sensor 1 oxygen sensor replacement
Bank 1 sensor 2 oxygen sensor replacement
Bank 2 Sensor 1 oxygen sensor replacement
Bank 2 Sensor 2 oxygen sensor replacement
Throttle body clean or replacement
Air filter replacement
Coil replacement
Coil boot replacement
Spark plug wire repair
Fuel system service
Mass air flow clean or replacement
Injector replacement
Computer program update
Fuel injector cleaning service performed
Upper intake decarbonization performed
Gas direct injection fuel service performed
Timing Belt Replacement
Radiator Replacement
Cooling System Fluid Exchange
Wiring harness replacement
Engine replacement
Radiator hoses replacement
Heater hoses replacement
Gaskets replacement
Seals replacement
Thermostat replacement
Coolant temperature sensor replacement
Sensor pigtail replacement
Instrument cluster replacement
Cooling fan replacement
Bypass hoses replacement
Cooling system flush
Serpentine Belt Replacement
Radiator hose replacement
Thermostat Gasket replacement
Thermostat Housing Replacement
Timing Belt Tensioner Replacement
Camshaft Seal Replacement
Crankshaft Seal Replacement
Crankshaft Balancer Replacement
Heater hose replacement
Bypass hose replacement
Radiator cap replacement
Water Pump Replacement
Spark plugs replacement
Wiring harness repair or replacement
Computer replacement
Throttle body replacement
Throttle pedal replacement
Timing chain replacement
Coil replacement
Coil boot replacement
Spark plug wire repair
Timing Belt Tensioner Replacement
Computer program update
Timing chain slide replacement
Timing chain tensioner replacement
Variable valve timing solenoid replacement
Variable valve phaser replacement
Cam sensor replacement
Crank sensor replacement
Timing belt idler replacement
Fuel pump replacement
Fuel filter replacement
Catalytic converter replacement
Head gasket replacement
Ignition Wire Replacement
Ignition coil boot replacement
Ignition Coil Replacement
Engine Mechanical Repair
Coil replacement
Coil boot replacement
Spark plug wire repair
Fuel system service
Mass air flow clean or replacement
Injector replacement
Module replacement
Valve Cover Gasket Replacement
Intake gasket replacement
Computer program update
Intake replacement
Timing Belt Replacement
Fuel injector replacement
Fuel pump replacement
Fuel filter replacement
Catalytic converter replacement
Mass air flow replacement
Computer Software update
Wiring harness repair or replacement
Computer replacement
Throttle body replacement
Timing chain replacement
Coil replacement
Spark plug wire repair
Vent valve replacement
Charcoal canister replacement
Computer program update
Fuel injector cleaning service performed
Upper intake decarbonization performed
Gas direct injection fuel service performed
Variable valve timing solenoid replacement
Variable valve phaser replacement
Cam sensor replacement
Crank sensor replacement
Vapor line replacement
Fuel pump replacement
Fuel filter replacement
Catalytic converter replacement
Head gasket replacement
Spark plug replacement
Coil replacement
Coil boot replacement
Spark plug wire repair
Fuel system service
Mass air flow clean or replacement
Injector replacement
Module replacement
Valve Cover Gasket Replacement
Intake gasket replacement
Computer program update
Intake replacement
Oxygen Sensor Replacement
Fuel injector replacement
Fuel filter replacement
Catalytic converter replacement
Spark plug replacement
Ignition Coil Replacement
Mass air flow replacement
Spark plugs replacement
Sensor pigtail replacement
Computer Software update
Wiring harness repair or replacement
Computer replacement
Fuel tank replacement
Fuel Line Replacement
Fuel pressure regulator
Fuel pump relay replacement
Fuel pump driver module replacement
Wiring harness replacement or repair
Vacuum line replacement
Fuel rail pressure sensor replacement
Exhaust system replacement
Mass Air flow sensor replacement
Throttle body replacement
Throttle pedal replacement
Computer module replacement
Air filter replacement
Coil replacement
Coil boot replacement
Spark plug wire repair
Fuel system service
Mass air flow clean or replacement
Injector replacement
Computer program update
Fuel injector cleaning service performed
Upper intake decarbonization performed
Gas direct injection fuel service performed
Variable valve timing solenoid replacement
Variable valve phaser replacement
Cam sensor replacement
Crank sensor replacement
Fuel injector replacement
Fuel pump replacement
Spark plugs replacement
Sensor pigtail replacement
Wiring harness repair or replacement
Computer replacement
Fuel tank replacement
Fuel Line Replacement
Fuel pump relay replacement
Fuel pump driver module replacement
Wiring harness replacement or repair
Vacuum line replacement
Fuel rail pressure sensor replacement
Throttle body replacement
Air filter replacement
Coil replacement
Coil boot replacement
Spark plug wire repair
Computer program update
Fuel injector cleaning service performed
Upper intake decarbonization performed
Gas direct injection fuel service performed
Cam sensor replacement
Crank sensor replacement
Oxygen Sensor Replacement
Fuel injector replacement
Fuel pump replacement
Fuel filter replacement
Spark plug replacement
Ignition Coil Replacement
Exhaust manifold replacement
Mass air flow replacement
Air fuel ratio sensor replacement
Intake gaskets replacement
Exhaust manifold gasket replacement
Exhaust Pipe replacement
Intake air temp replacement
Spark plugs replacement
Spark plug wires replacement
Coils replacement
Computer Software update
Wiring harness repair or replacement
Computer replacement
Mass Air flow sensor replacement
Throttle body replacement
Throttle pedal replacement
Bank 1 sensor 1 oxygen sensor replacement
Bank 1 sensor 2 oxygen sensor replacement
Bank 2 Sensor 1 oxygen sensor replacement
Bank 2 Sensor 2 oxygen sensor replacement
Throttle body clean or replacement
Air filter replacement
Coil replacement
Coil boot replacement
Spark plug wire repair
Fuel system service
Mass air flow clean or replacement
Injector replacement
Computer program update
Fuel injector cleaning service performed
Upper intake decarbonization performed
Gas direct injection fuel service performed
Water Pump Replacement
Timing Belt Replacement
Cylinder Head Replacement
Cooling System Fluid Exchange
Engine Oil change Service
Timing Belt Replacement
Fuel injector replacement
Fuel pump replacement
Fuel filter replacement
Catalytic converter replacement
Mass air flow replacement
Computer Software update
Wiring harness repair or replacement
Computer replacement
Throttle body replacement
Timing chain replacement
Coil replacement
Spark plug wire repair
Vent valve replacement
Charcoal canister replacement
Computer program update
Fuel injector cleaning service performed
Upper intake decarbonization performed
Gas direct injection fuel service performed
Variable valve timing solenoid replacement
Variable valve phaser replacement
Cam sensor replacement
Crank sensor replacement
Vapor line replacement
Fuel pump replacement
Fuel filter replacement
Catalytic converter replacement
Head gasket replacement
Spark plug replacement
Coil replacement
Coil boot replacement
Spark plug wire repair
Fuel system service
Mass air flow clean or replacement
Injector replacement
Module replacement
Valve Cover Gasket Replacement
Intake gasket replacement
Computer program update
Intake replacement
Oil filter replacement
Oil Pan Gasket Replacement
Oil plug replacement
Oil plug gasket replacement
Oil pan replacement
Timing cover replacement
Oil filter housing gasket replacement
Crankcase vent valve replacement
Oil pressure sending unit replacement
Fuel injector replacement
Fuel pump replacement
Fuel filter replacement
Spark plug replacement
Vacuum hose replacement
Gasket replacement
Throttle body replacement
Coil replacement
Coil boot replacement
Spark plug wire repair
Idle air control valve replacement
Intake replacement
Valve job
PCV valve replacement
Dipstick replacement
Fuel injector service
Upper intake decarbonization
Brake Lining Replacement
Brake Lining Wear Sensors Replaced
Brake Rotor Replacement
Brake caliper replacement
Brake System Fluid Exchange
Brake System Fluid Flush
Brake Shoe Replacement
Wheel bearing replacement
Brake fluid exchange
Rotor replacement
Wheel bearing repack
Brake hose replacement
Wheel cylinder replacement
Brake fluid flush
drum replacement
Resurface drums
Resurface rotors
Brake cable replacement
Brake shoes replacement
Brake rotors replacement
Brake drum replacement
Hand torque wheel lug nuts in a star pattern
Axle Seal Replacement
Brake Pad Replacement
Brake Rotor Replacement
Brake Shoe Replacement
Wheel bearing replacement
Rotor replacement
Wheel speed sensor replacement
Brake hose replacement
Emergency brake cable replacement
Brake fluid replacement
Brake pad slides cleaned and lubed
Brake caliper slides cleaned and lubed
Brake line replacement
Wheel cylinder replacement
Brake fluid flush
drum replacement
Resurface drums
Resurface rotors
Brake cable replacement
Brake rotors replacement
Brake drum replacement
Hand torque wheel lug nuts in a star pattern
Brake hardware replacement
Brake Pad Replacement
Brake caliper replacement
Brake Shoe Replacement
Tire replacement
Rotor replacement
Brake hose replacement
Wheel cylinder replacement
Brake fluid flush
drum replacement
Resurface drums
Resurface rotors
Brake cable replacement
Why? Little to no environmental impact is present
Transaxle Output Shaft Seal Replacement
Axle Shaft Seal Replacement
Axle Bearing Replacement
Axle Shaft Replacement
Differential Fluid Exchange
Wheel Replacement
Constant Velocity Drive Axle Replacement
Differential Output Shaft Seal Replacement
U-joint replacement
Drive shaft replacement
CV axle replacement
Drive shaft support bearing replacement
Below are just a few examples of typical Symptoms and Fixes your car might be experiencing