When you are riding your ATV, you expect it to run smoothly. If your ATV sputters, it can be extremely concerning, especially when you don’t know why it’s happening. So, what makes an ATV sputter?
An ATV could sputter because it has too much oil, the fuel is contaminated, the oil filter is dirty, or the air filter is loose. The ignition coil or spark plug may also need to be replaced. An ATV could also start sputtering if the oil needs to be changed or the carburetor needs to be inspected.
Keep reading to learn about the reasons why your ATV may be sputtering and what to do about it.
Overly Full of Oil
The oil tank being too full is a leading cause of sputtering noises and ATV engine issues. You may be able to solve this issue by changing the oil. Measure out how much oil is recommended for the specific brand and make of ATV, especially since some ATV oil gauges can be difficult to read.
The ATV will have an oil dipstick that is very similar to an oil dipstick in a car, just smaller. To check the oil, you will first want to make sure the ATV is at a neutral temperature. If you just rode it, wait for the engine to cool down. Then, pull out the dipstick and wipe it off with a paper towel to get it clean.
Replace the dipstick for a second before removing it again. This time, look at where the oil stops. The oil level should be in between the maximum and minimum lines. The area is often marked with hashes.
If there is too much oil in your ATV, you can drain a small amount of oil into a drain pan or get a full oil change. Check the oil level again after correcting the issue to make sure it isn’t too low.
Your ATV may also be sputtering because the oil needs to be changed even though the oil level in your ATV is within the normal range. If it has been too long since your last change or the oil is very dark in color, it is time for an oil change.
Fuel is Contaminated by Oil
The fuel in the ATV can get contaminated by oil, which leads to sputtering noises and engine complications. This could occur because of leaks or damage within the vehicle.
Fuel contamination is one of the reasons why most professionals advise ATV owners to perform an initial oil change after 10 hours of ATV riding.
Never try to operate or start up an ATV, or any vehicle for that matter, that has a fuel leak. Leaked fuel can easily ignite and lead to a dangerous explosion or malfunction.
This isn’t usually a DIY fix. Take your ATV to an auto shop, as they will be able to safely repair any leak or damage.
Air Filter
A slightly less likely reason for an ATV to be sputtering includes a dirty air filter! This cause isn’t at the top of the list because most new ATVs–and new air filters–are not likely to have technical issues. However, an air filter can become clogged and dirty if you live in a very dusty area or if you forget to clean or replace it after a few years.
Air filters are extremely easy to clean and replace. If your ATV has started sputtering, you will probably just need to replace the filter. After replacing it, make sure to clean it regularly.
If the air filter is not dirty, the sputtering may be caused by gas getting into the filter or the filter getting damaged or unplugged. The air filter will need to be inspected or replaced entirely to prevent bogging down in the ATV. Check your air filter for holes or tears and make sure that all of the connections are secured.
Carburetor Needs Inspection
One of the most common causes of sputtering in an ATV is carburetor issues. This is because carburetors are an older type of technology, offering an ideal combination of fuel and air that ATVs need as a power source. Carburetors, like any other type of technology, can have performance issues. If there is a carburetor problem, it usually takes the form of a gas leak, a vacuum leak, or a tuning problem.
The sputtering may also be caused by a dirty ATV. Semi-blocked airflow in and around the carburetor can create a sputtering sound. Users of the Suzuki ATV Help Forum advise giving the carburetor a good cleaning while inspecting it. Regularly cleaning your ATV is a good idea since the high-speed jet could be clogged and cause your ATV to sputter.
Additionally, during a carburetor inspection, the main jet component should be checked. The jet should be laying in the bowl sp the ATV can run correctly. The vent tube also must be double-checked to determine if it is blocked or not. If the vent tube has a blockage, it will need to be carefully cleared of debris and buildup.
Give the carburetor a deep clean to help make sure these components are not the source of the sputtering. Changing and adjusting jets, changing out the fuel pump, adjusting the float in the carburetor, and cleaning the carburetor could make the sputtering sounds stop.
Tuning
If the carburetor isn’t tuned correctly, your ATV could start sputtering. When the ATV’s carburetor is not adjusted correctly, it will likely lead to the air screw and fuel screw’s balances becoming unaligned from each other. This is a very delicate process that should not be fixed at home. Take the ATV into a repair shop to have it tuned by a professional. After a carburetor tuning, the ATV’s sputtering should end.
Gas Leak
When gas leaks occur in carburetors, the engine can get starved for gas as a result. This is the most obvious cause of sputtering in ATVs. In order to fix it, you will need to figure out what caused the leak in the first place. Usually, a brittle or cracked gasket above the float bowl in the bottom of the carburetor is where most gas leaks originate.
The smell of gas burning can indicate a gas leak as the cause of a sputtering ATV. Burning gas also usually produces dark smoke. The easiest way to diagnose gas leaks is to replace the float bowl gaskets in your ATV and make sure to replace any cracked or broken gaskets! An auto repair shop can help you determine the exact location of the gas leak.
Vacuum Leak
Pesky vacuum leaks can occur in ATVs whenever the intake boots get brittle, damaged, or cracked. The clamp surrounding the intake boots could also get too loose between the carburetor and the engine of the ATV. This leads to the carburetor not creating enough air for the air-fuel mixture, causing sputtering. You can fix this issue by replacing their intake boots. Luckily, intake boots are pretty easy to replace because they are fairly cheap and inexpensive, and most owners can perform this replacement themselves!
Fuel Petcock Needs to be Changed
Some long-time ATV owners and users have had issues with their fuel petcock causing their ATVs to sputter. Any issues or blockages with the fuel petcock are a problem since they can starve the ATV engine of fuel, leading to engine start issues and sputtering sounds. By changing the fuel petcock, many owners have reported that the sputtering stopped soon or immediately after.
Spark Plug Needs to be Replaced
For some ATV owners, all they need to do is change out an old spark plug for a new one to make their ATV stop sputtering. Sometimes, the spark plug can become too old, blackened, or have unburned fuel on it from overuse, wear and tear, or damage. If a spark plug looks beat up, or if it has not been changed in a long time, this is a good indicator that it is the cause of your ATV sputtering. Replace the spark plug or have a mechanic at an ATV repair shop do so to fix the ATV.
The Ignition Coil Needs to be Replaced
Faulty ignition coils can also make an ATV start sputtering. Malfunctioning or bad ignition coils will not send enough sparks into the vehicle’s spark plugs, causing the ATV to misfire and then sputter. The misfiring of the engine is your best indicator that the sputtering is caused by the ATV’s ignition coils. To fix the issue, replace the ignition coils.
Loose or Broken Air Screw and/or Fuel Screw
Some ATV experts will advise that a loose or faulty air screw could be the reason for ATV sputtering. If this is the case, you may also hear a faint rattling at the same time. If the air screw and fuel screw’s balances are out of line with each other, you will need to readjust these parts of the carburetor or have them adjusted in a mechanic’s shop.
Dead Battery or Battery Issues
It is always a good idea to try the battery on an ATV to see if that is the cause of random or persistent sputters. The battery is a key component of any vehicle, as it is responsible for providing a lot of power to the machine. The ATV can occasionally get started with a pull rope and idle without sputtering, but if the owner gives it some gas, the ATV will usually sputter and then die unless the driver lets off the gas pedal.
If an ATV does not have enough battery, the ATV will not start. First, try recharging your ATV’s battery if you have access to the charger. If you are not able to charge it, get a jump start from another ATV. You will want to use another ATV and not a car to jumpstart your ATV, as car batteries are much more powerful than ATV batteries. Run the ATV for a while to allow the battery to recharge.
It is pretty common for ATV batteries to die if you have not ridden the ATV in a while. The battery needs consistent use to keep up the charge.
If the jump start does not work, you can try recharging the battery. If this also fails, you may need to replace the battery entirely. The age of your ATV may be a good indicator of whether or not the battery is having issues. Different types of batteries last different amounts of time. Most ATV owners will need to replace a battery at some point.
Lithium iron phosphate batteries are the most durable type of batteries and shouldn’t need to be replaced until after being used for about 9 or 10 years. AGM batteries wear out much faster, as they only last about 3 to 5 years. If your ATV has a lead acid battery, it will likely not last longer than 3 years, and you will have to replace it consistently.
Faulty Spark Plug Wires
If an ATV is relatively old, it can have complications arise due to the spark plug wires that connect to the spark plugs. When these issues happen, sputtering will often start as a consequence. If the connection head is correctly attached to the spark plug wire, the ATV may be alright. However, if the spark plug wires have become corroded or disconnected over time due to use, they may need to be changed out and replaced so they continue working.
To change out old spark plug wires for new ones, pull the old ones apart and carefully un-thread them. Clean up the wires, snip them, then rethread them and connect them back to their original connections. Don’t forget to check for any possible cracks in the spark plug or wires. ATV owners can replace their spark plug wires relatively easily if the old ones have any cracks or punctures.
Overall, many things can make your ATV sputter. Unfortunately, this means that you will likely have to fix or test multiple things to determine what is making your ATV sputter.