Engine Sputtering: Common Causes and Solutions
Car owners know how essential their vehicles are to their everyday lives. They offer the convenience of getting to work early and not missing crucial family dinners.
However, we can take our vehicles for granted sometimes and fail to cater to them. After all, if it’s not broken, don’t fix it right?
Unfortunately, treating our cars this way can lead to major mechanical issues, such as engine sputtering. Eventually, you’re left executing fixes you could’ve avoided.
Common Causes and Solutions for Engine Sputtering
1. Gas Shortage
Engine sputtering isn’t always a sign of serious engine trouble. Often, you’ll find your engine sputtering whenever you’re running out of fuel, and your car might eventually stop running after a while.
When you notice a sputtering engine, check your fuel gauge to determine if you’ve got enough fuel in the vehicle. If you don’t, it’s time for a refuel. However, a sputtering engine on a fuel-filled vehicle points to a more significant issue.
2. Damage Spark Plugs
Your vehicle’s spark plugs create the sparks for fuel combustion. When they’re worn out or damaged, they can’t provide ideal combustion, and your engine may sputter.
However, worn-out or damaged spark plugs aren’t the only cause of engine sputtering. Dirty spark plugs also cause an engine to sputter because the vehicle won’t get clean combustion. Thus, you’ll need to clean them to fix the problem.
However, if your spark plugs are worn-out or damaged, get new ones as soon as possible. It’s easier to replace them individually when they’re in the early damage phases. If the fault is more significant, take the vehicle to a mechanic.
3. Dirty Fuel Injectors
Automobile fuel injectors spray gas into the combustion cylinders. The fuel then mixes with the air and ignites. However, your car’s fuel injectors can become dirty and clogged with time. As such, fuel won’t move smoothly into the combustion chambers, leading to engine sputtering and poor acceleration.
If you notice a sputtering engine, it may be time to clean your fuel injectors, although this may void your car’s warranty. You may also consider replacing them if they’re beyond cleaning.
Another reason you might consider getting new fuel injectors is if you’re struggling to accelerate up hills. Nonetheless, whether you’re replacing or cleaning your fuel injectors, ensure you hire a reliable mechanic.
4. Dirty Air Filters
Dirty air filters reduce the quantity of air that gets to your engine. In turn, you’ll have higher unburnt fuel, which becomes soot residues that clog your spark plug tips.
Your spark plugs will fail to provide ideal combustion sparks, which eventually causes the engine to sputter. If your car’s air filters are dirty, it’s time to clean them up or replace them, depending on the damage.
5. Throttle Damage
If your throttle isn’t closing properly, air will escape from the opening without ideal filtration by the Mass Airflow Sensor (MAF). As such, you’ll end up with too much air in the fuel combustion mixture and a sputtering engine. Your engine’s throttle is another component you need to have checked when your engine begins to sputter.
6. Exhaust Manifold Leaks
Leaks in your exhaust manifolds could result in engine sputtering. The exhaust manifold collects exhaust fumes from the engine cylinders and carries them to the catalytic converter. When it’s faulty, your engine may perform poorly.
You’ll also notice unusual engine sounds and a flashing “Check Engine” light. Driving with a leaking exhaust manifold is also dangerous. The hot gasses that escape may melt any plastic component nearby, and exhaust fumes might end up in your car cabin.
7. Faulty Catalytic Converter
Your catalytic converter burns the exhaust fumes’ dangerous hydrocarbons. It may struggle to execute this task when it’s faulty. When this scenario happens, you’ll notice a sputtering engine and a rotten egg smell. Your Check Engine light may also come on.
Additionally, a failing catalytic converter can result in more significant engine damage, especially when it’s clogged totally. In several cases, your car fails to start completely. Having a mechanic look at your catalytic converter could solve any engine sputtering issues you’re having.
8. Vacuum Leaks
A leak in your vehicle’s vacuum hoses can create an imbalance in the engine fuel and air mixture. You may end up with too much air and inadequate fuel in the engine (otherwise called lean fuel mixture).
As such, your engine may sputter while accelerating or in motion. Often, the vehicle may stall when you stop the automobile. You may also notice a flashing Check Engine light.
Furthermore, the needle on your tachometer may become unstable due to sporadic RPMs prompted by bursts of air from the vacuum leak. Finally, you may hear suction noises from the engine.
9. Ignition Coil Issues
Your ignition or spark coil transforms your car battery’s 12 volts into the required voltage amount required to kick start the spark plug’s ignition and eventual fuel combustion. Without the ignition coil, your spark plug won’t ignite, and there’ll be no fuel combustion to start the vehicle.
However, if your ignition coil is faulty, you may experience several issues with your vehicle, including your engine failing to start or sputtering while in motion.
This sputtering can increase emissions, and you’ll often notice a gaseous smell from your exhaust. Gas odors from your exhaust are often signs of a faulty ignition coil. Your Check Engine light might also flash to indicate the troubles with your engine compartment.
10. Leaky Seals/Gaskets
Your vehicle features numerous seals/gaskets throughout its fuel, transmissions, cooling, exhaust, and engine system. A leak or fault in these seals can result in a sputtering engine.
Alongside a misfiring engine, you may also notice strong odors and fumes from underneath the vehicle.
This gas smell often indicates a leak in the exhaust system gasket but may also point to other issues. Regardless, these fumes are toxic to your health. You should check and replace your car’s seals and gaskets over time. If you don’t maintain them regularly, you risk damaging the exhaust manifold, and that could lead to a costlier repair.
11. Faulty Oxygen Sensor
Your car’s oxygen sensor measures the oxygen levels of the fumes that leave the exhaust. The Powertrain Control Module uses these details to determine the ideal fuel-to-air ratio the vehicle needs.
The oxygen sensor is usually located in the exhaust system. Alongside fuel injection, it also plays crucial roles in emissions control. A damaged oxygen sensor could result in too little or too much fuel finding its way to the engine, which could cause it to sputter and affect its overall performance.
Your Check Engine light will also notify you about the issues in the exhaust system. Furthermore, the vehicle could have reduced gas mileage.
Additionally, you’ll notice a rotten egg or sulphuric smell and black smoke coming from the exhaust. These gas emissions can have negative environmental impacts.
Loss of power and engine stalling are other symptoms of a faulty oxygen sensor. If you notice these signs, it’s definitely time for engine sputtering maintenance.
12. Damaged Fuel Filters
Fuel filters remove harmful fuel particles that could damage your vehicle’s engine. These filters are vital components of automobiles with internal combustion engines. However, they can become clogged or dirty over time and fail to carry out their duties efficiently.
Clogged fuel filters may even restrict fuel flow if the dirt in their components is excessive. A common symptom you may experience with a dirty fuel filter is engine sputtering. The clogged filter reduces the amount of fuel that gets to the engine, leading to a misfiring engine while you’re trying to accelerate or in motion.
In some cases, the restricted fuel flow may hinder the car from starting completely. You’ll likely experience this scenario if you’ve never changed or cleaned your fuel filter since you purchased your vehicle.
Furthermore, you may end up with a damaged fuel pump. A clogged filter often results in excessive pressure on the fuel pump, which might damage it. You’ll also notice a flashing Check Engine light.
13. Clogged Mass Airflow Sensor
Your vehicle’s Mass Airflow Sensor (MAF) calculates the amount of air that gets into the engine to ensure the engine control module maintains the ideal balance of fuel and air in the combustion chambers.
However, this component can also get clogged or dirty and lose efficiency. When your car’s MAF is dirty, you may notice a sputtering engine due to the imbalance of fuel and air in the vehicle. This sputtering is tell-tale of excessive air in the combustion chamber.
The excessive air may also cause your car to struggle to start. Furthermore, reduced fuel economy and rough idling are some more symptoms you’ll notice with a dirty MAF.
As usual, your Check Engine light will also come on.
14. Damaged Coolant Temperature Sensor
Your car’s coolant temperature sensor (CTS) measures the engine control module’s coolant temperature and uses this information to regulate the air-fuel mixture. It also measures the overall temperature of your engine.
However, if faulty, you may experience poor engine performance, such as engine sputtering.
Besides a sputtering engine, your car might not start due to the “fuel-to-air” imbalance. This imbalance may also result in improper combustion, which could lead to black smoke emissions from your exhaust.
Furthermore, your engine may also overheat when the CTS suffers damage. This scenario happens when the cooling fan receives the wrong signal from the onboard computer due to a faulty coolant temperature sensor and fails to start.
You may notice a damaged water pump, as well. A faulty coolant temperature sensor will often read wrong engine coolant temperature ratings.
When it reads higher temperature figures different from the actual rating, the engine will try to correct the temperature rise by increasing the water speed from the water pump. As a result, your vehicle’s water pump may experience unnecessary strain and end up damaged.
You may notice other symptoms, including reduced gas mileage, poor idling, and reduced overall engine efficiency.
15. Faulty Idle Air Control Valve
The idle air control valve controls the quantity of air that gets to your vehicle’s engine while idling. In other words, it determines the ideal air amount for a steady idle speed. When the idle air control valve fails, your engine might sputter due to an improper air-to-fuel ratio.
You might also struggle to start the vehicle. In many cases, the car might start, then stop immediately after the engine is starved of air.
However, the most common symptom you’ll experience is irregular idling speed.
The idle air control valve works to maintain a regular idle speed. When it’s faulty, you’ll notice unusually high or low idling speed. Your Check Engine light will also notify you when there’s an issue with the idle air control valve.
However, since the Check Engine light can come on whenever there’s a fault with any aspect of the engine compartment, it’s best to have a mechanic look at your car before jumping to conclusions.
16. Contaminated Fuel
Contaminated fuel often contains microbial growth (diesel bugs) or water. The microorganisms in the fuel may also leave excrements, further eroding its quality.
Having contaminated fuel in your vehicle can lead to engine sputtering. You may also notice rough starts with your engine alongside a lack of engine power. Furthermore, your engine tank might show signs of corrosion. Contaminated fuel might also damage your fuel injectors, filters, and fuel pump.
Engine sputtering occurs from multiple factors. The most common and least worrying is a lack of fuel in the engine. However, your engine might also sputter when you have dirty air filters, faulty ignition coils, leaky gaskets, or a damaged catalytic converter.
Any of these issues could lead to significant engine damage if you don’t attend to them early. As such, when you notice a misfiring engine that’s not due to an empty fuel tank, it’ll be best to visit your mechanic immediately for an engine sputtering repair.
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