Why Does ATV Backfire and How to Fix It?

Last Updated on November 23, 2023 by ATVNotes

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Have you ever suddenly heard a loud pop or bang while riding your ATV? Chances are that your ATV has started to backfire. Although ATV backfiring is common, you might feel helpless if you are a first-time owner. And even veteran off-roaders have their mood ruined when startled by a sudden and sharp jolt or a complete halt while on the run. Typically, ATV backfiring is caused when an imbalanced mixture of fuel and air is sparked out of the combustion chamber. In most cases, ATV backfiring occurs in the exhaust pipe or engine’s intake section and can shut your model off. To learn more about why ATVs backfire, how to fix ATVs backfire, and so forth, read this article. 

What is Backfiring, and When is It Alarming? 

Before we discuss what causes an ATV to backfire and the fixing hacks, you must first understand what is backfiring in a vehicle. Encountering a loud pop or bang while riding your favorite off-road four-wheeler is not a matter of concern. But if it happens now and then and makes your running engine stall suddenly, you must take it seriously. It may happen in the middle of a ride or while trying to start your ATV. That frequent stalling or loud popping is backfiring, resulting from a mistimed explosion outside the combustion chamber of your car engine. 

Right air fuel ratio in your ATV

ATV, a vehicle meant for running mostly on off-highway trails, has an internal combustion engine, just like a typical car or truck. If combustion happens outside the ATV engine combustion chamber – in the intake pipe or the exhaust, your ride will start halting from time to time. You may be startled by the sharp jolt and jump along the machine. You may encounter an engine stall while trying to start. This is ATV backfiring – the last thing you want to encounter when enjoying wild seclusion or lost in the natural setting of faraway off-street curves. 

To rephrase it in technical language, backfiring happens when the ATV’s engine ignites the fuel in your ATV’s exhaust system instead of doing so in the combustion chamber. In fact, the aftermath of that combustion is known as backfire, as the ATV’s internal combustion engine causes a sudden loud explosion.

During this process, your engine might fail or even shut down altogether since your engine lacks enough fuel at that moment.

Although your engine might shut down during backfiring, re-igniting your ATV can get it up and running afresh. However, if you ignite your ATV’s engine and it backfires again, an underlying problem must be solved. Some operators complain that ATVs backfire when trying to start. Let’s examine the causes of why your ATV may backfire. 

Why does my ATV backfire-Various Reasons

As explained above, the ATV backfire, or afterburn, primarily can be attributed to the combustion chamber’s imbalanced air and fuel mixture. Other reasons may cause the crucial spark outside the chamber what is supposed to happen inside it. I will describe all the reasons why your ATV backfires now and then:

1. Presence of a lean or rich fuel/air mixture

For your ATV engine to work optimally, its combustion chamber needs to receive a balanced mixture of air and fuel. Once a spark plug ignites this mixture, your engine generates the much-needed power to propel you forward. However, there are instances when your engine’s combustion chamber can get too much fuel and very little air.

As a result, some fuel might find its way to the exhaust pipe or outside the combustion chamber. Once this happens, your engine’s spark plug will still ignite this fuel, leading to a loud bang or pop sound.

Besides having too much fuel and little air in the combustion chamber, there are scenarios of a lot of air and little fuel in the same chamber. This, too, creates an imbalance of the most important components needed to power up your ATV’s engine. As a result, your ATV might backfire, letting out a loud explosion once you start your engine.

2. Your ATVs carburetor is clogged or faulty

Besides having an imbalanced mixture of air and fuel in the combustion chamber, your ATV might start backfiring or not starting at all if its carburetor is either clogged or faulty. Such is the case if you have not driven your ATV for quite some time. 

Fine tune the ATV carburetor

If this happens, the fuel inside your ATV’s tank might start degrading, and once you start driving your ATV, this fuel might end up clogging your carburetor. Consequently, your engine will be starved of fresh air, creating an imbalance of fuel and air ration in your engine’s combustion chamber.

3. You made changes to your ATV’s exhaust pipe or muffler

If you modify your ATV’s exhaust or muffler, the operation of your model’s fuel and exhaust system might get altered, thereby making your ATV backfire.

4. Presence of low or weak pressure from your ATV’s fuel pump

Apart from the issues we discussed above, your ATV might start backfiring if there is little fuel allowed to get into your engine’s combustion chamber. If this is the case, some fuel might be ignited outside the combustion chamber or in the exhaust, making your model start backfiring. Such a problem occurs when there is low or weak pressure from your ATV’s fuel pump.

5. Your engine is faulty, or your ignition is faulty

If your ATV’s engine or ignition is faulty, be certain that your model will start backfiring. However, these two issues are quite different. For instance, if your ATV’s engine is faulty, it can be hard to tell and can damage other vital components of your ATV. On the other hand, a faulty ignition can easily be fixed, thereby solving the backfiring problem.

For many users, if the ignition is the issue, you might be prompted to purchase new spark plugs. Although this might work magic, the problem might persist at other times. The latter is since the plugs might continue to ignite the fuel in the exhaust or intake section, thereby making your ATV backfire every now and then, despite the changes made.

Other times, the ignition might be firing at the wrong moment due to faulty coils, spoilt connectors, and damaged high-tension leads, among other issues. Thankfully, these issues can be dealt with, thereby solving the backfiring problem once and for all.

On the other hand, if your ATV’s engine is faulty, chances are that there is a leak or a major component of your engine has been broken. A good example is when your muffler or exhaust pipe has a crack. 

Other times, your engine might have a lean idle circuit. Additionally, your engine might have delays. Here, your engine’s cylinder head may fail to get into synch with your ATVs exhaust system. Since these components should work hand in hand, any delay in their syncing can make your ATV’s engine ignite later than the correct time. With all these issues, fuel and airflow might be altered, thereby creating an imbalance in the combustion chamber. The aftermath of this phenomenon is backfiring.

How to fix backfiring on ATV? – 5 Fixes

The last thing you want while riding ATV is frequent backfiring. Thankfully, this issue can be solved through a number of methods. Some of the practical solutions to these problems include:

1. Use high-quality fuel

It is no secret that the kind of fuel that you use on your ATV can affect its performance. For instance, if you are using old or low-quality gas, be certain that your ATV’s performance will no longer be optimal. Here, it might start backfiring, among other problems. To avert this problem, you should invest in superior quality fuel so that its engine can perform excellently.

2. Ensure that you clean your ATV’s carburetor and fuel injector

Apart from using high-quality fuel, you can fix the backfiring problem on your ATV by cleaning its carburetor and fuel injector. As we mentioned above, these components can become faulty or clogged from time to time.

Fix Fuel injector

If this happens, they will be unable to release the much-needed air and fuel mixture needed for combustion. However, once you clean these components, you can keep the backfiring issue at bay. Thankfully, high-end solutions can help you clean these components more effectively.

Having said that, carburetor cleaning is a mechanical task requiring component removal and getting the carburetor jets disassembled. If you are a simple DIYer without basic mechanical background, you better invest in professional cleaning.

3. Keep an eye on your air and fuel filters

As we mentioned above, one problem that might cause your ATV to backfire is when there is an imbalance of air-fuel mixture in the combustion chamber of your model’s engine. One problem that can lead to this is faulty air and fuel filters.

Such is usually the case if these components get clogged or blocked by unwanted elements such as mud, dirt, etc. This is why you should keep an eye on them and even change them when necessary. Consider changing them once in a while so that your ATV can stop backfiring persistently.

4. Check the throttle settings of your ATV

Besides the measures we discussed above, consider checking your ATV’s throttle settings, and you will be able to mitigate the backfiring problem more effectively. Here, you should look out for the throttle wheeler in your ATV model and then make the much-needed adjustments so that they can suit your engine’s performance.

With the throttle wheeler, you will be free to either increase or decrease the fuel that gets into your engine when it is idle. Once you make these adjustments, you can examine your engine’s response to those changes as you drive your ATV.

Check ATV throttle setting

5. Hire the services of a professional ATV mechanic

If you have tried all the ideas mentioned above and none has borne fruit, consider hiring a professional ATV mechanic. Unlike you, who have little or no knowledge of ATV engines, the professional knows more and has all the competencies needed to complete the work. All you need to do is to contact your professional mechanic and then narrate your story. The professional on the other end will diagnose the backfiring issue and fix it accordingly.

Is backfire dangerous for your ATV? – Get Rid of It

Well, it depends on the number of times your ATV backfires. For instance, if your ATV backfires occasionally, you have no reason to worry about it. However, if your model keeps backfiring off and anon, you should consider fixing this problem once and for all. This is because constant backfiring can damage your ATV’s exhaust system. If this continues unaddressed, you might dig more into your pocket since other components can get damaged.

From the article above, it is clear that your ATV can start backfiring for several reasons. Whether it is an imbalance in fuel and air mixture or engine delays, there are many reasons why your ATV can backfire frequently. The good news is that all these issues can be mitigated using the ideas that we have mentioned above. Now that you know why ATVs backfire, implement these ideas today, and your ATV will not backfire anytime soon.

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