A Guide to ATVs with Fuel Injection – EFI ATVs

Modern ATV with fuel injection engine, riding on a road.

It has been over a few decades since the incorporation of fuel injection systems in ATVs. Carburetors have become antique and almost every ATV now has an electronic fuel injection system. So, what ATVs have fuel injection, and which one has carburetors? Is there any difference?

These days, almost every quads that you find around are fuel injected. That’s because of the reliability they offer and the increasing environmental regulations. With the introduction of EFI technology, the use of carburetors has been a matter of the past. While some people advocate for carburetors even today, the number is low.

What is EFI and how does it work?

Traditional engines needed a carburetor to mix fuel and air. However, the introduction of electronic fuel injection or EFI replaces the need for a carburetor. In short, EFI does what it sounds like. The system injects fuel into the engine’s cylinder or manifolds directly by using certain electronic components. 

Although the auto industry is greatly benefited from this technology, it is not common in small engines. An electronic fuel injection system consists of sensors, fuel injectors, fuel pump, and ECU or Engine Control Unit. The fuel pump helps the fuel flow out to a fuel injection rail from the tank. It is then pumped to individual injectors and they are directly inserted into the engine’s manifold. And, the fuel injectors are controlled by the Engine Control Unit. 

ATV models that have EFI

Here are some of the ATVs models that come equipped with an electronic fuel injection system. 

However, the ATVs that have an electronic fuel injection system need a battery to keep the engine running. Also, there must be enough voltage in the battery so that it can produce a spark with the ignition coil in place. As little as 6 volts is needed and anything below that won’t let the engine run. 

Fuel injection in other vehicles

Typically, fuel injection in vehicles consists of four different types. The fuel injection types that you find in other vehicles include the following. 

Throttle-body or single-point injection

It is the simplest and earliest type of fuel injection. A throttle-body injection replaces the carburetor with a couple of fuel injectors in the engine’s air intake manifold. A single-point injection for many manufacturers was a revolution to the existing and more complex multi-point fuel injection. The system has better control compared to a carburetor. Also, it is easy to service and less expensive.

Multi-point fuel injection

A separate injector nozzle is connected to each cylinder outside the intake port in a multi-point fuel injection system. Injecting the fuel into the intake makes sure that it is drawn into the cylinder. The multi-point fuel injection system eliminates every chance of the fuel getting collected inside the intake manifold. 

Sequential fuel injection

Sequential port fuel injection (SPFI) or sequential fuel injection is a different type of multiport fuel injection system. Multi-point fuel injection systems employ a few injectors and they spray the fuel at the same time. As such, the fuel tends to accumulate around a port for about 150 milliseconds when the engine becomes idle.

While this doesn’t seem much, engineers have successfully addressed the situation. With sequential fuel injection, it triggers every nozzle separately. Because of that, the fuel gets sprayed immediately when the intake valve opens. That way, it paved the way for further improvements in terms of emissions and efficiency.

Direct injection

With a direct injection system, the fuel gets directly injected into the combustion chambers near the valves. While it is common in a diesel engine, the direct injection has attracted engineers and they have incorporated the same technology in gasoline engines as well. Fuel metering is more precise compared to other injection systems. Direct injection systems provide engineers with a variable option to know how combustion happens in all the cylinders. Besides, the direct injection can be used in lean-burn low-emissions engines. 

Carburetor vs fuel injection

Pros of carburetor

Although the EFI system took over the auto industry by storm, it doesn’t mean that carburetors are at the brink of extinction. In certain areas such as DIY and motorsports enthusiasts, carburetors are favored more than fuel injection systems, and for good reasons. And, because of these reasons, carburetors aren’t going to perish for a while. Carburetors:

  • Last longer than EFI system
  • Doesn’t require specialized training or equipment to fix
  • Don’t require any kind of electric work 
  • Are easy to install 

A carburetor is a mechanical device that doesn’t have any kind of electric components inside them. As a result, it is likely to wear and tear compared to the delicate and fragile circuits present in an electronic fuel injection system. That way, it is less expensive to install in an ATV.

An EFI system requires cylinder construction that needs to fall in line with the fuel tank. Whereas, a carburetor can be assembled by using a few hand tools. These are the reasons why carburetors are likely to go away anywhere. Because their pros are in large number intended for a specific group of people, they won’t overtake the EFI system.

Cons of carburetor

As said, carburetors are popular among the DIY types and hobbyists, they will fail to keep up with the changing and evolving demand in terms of different types of the air-fuel mixture. And, that’s where EFI will rise high. Besides, carburetors put out more smoke compared to the EFI systems and cause great concern to the environment. Here are some of the important disadvantages of using a carburetor system. 

  • There is no doubt that carburetor-powered vehicles require a significant amount of time to build. Hence, keep that in mind if you are planning to buy an ATV.
  • If you are someone who wants an ATV that performs well and don’t need extra efforts to put into it, an ATV with a carburetor isn’t recommended at all.
  • Because carburetors don’t have electronic components and are mechanical, they need more troubleshooting and tinkering compared to the EFI systems, which are flexible and reliable.

Pros of EFI systems 

Increased power along with better fuel efficiency and fewer emissions is what makes an EFI system a better option than a carburetor. EFI systems are popular because of their ability to adjust according to the fuel temperature, inclines, and weather. The system allows to sending off the right amount of fuel-air mixture to the cylinders. Also, it doesn’t need to be adjusted manually for varying conditions. Some of the pros include the following.

  • An EFI system reduces the chances of running an air-fuel mixture that’s either lean or rich because it continuously keeps track and regulates the right amount of fuel. 
  • An EFI system is far more effective in making an engine start even in cold weather.
  • You don’t have to constantly deal with a choke or adjust jets in an EFI system. The computer does that for you.
  • An ATV with a carburetor has issues while starting in a cold climate and need extensive use of the choke.

The EFI system allows you to know how much air-fuel mixture to push into the cylinders so that the engine starts and runs. 

Cons of an EFI system

While they are reliable, an EFI system can fail sometimes. Here are some disadvantages of having an EFI system.

  • Regular engineers can’t diagnose or repair an EFI system even in mechanic workshops. It is not possible to rebuild an EFI system with an ordinary mechanic.
  • A great deal of specialized equipment and training is required to fix an electronic fuel injection system. As such, the repairing and maintenance costs are usually higher. 

Fuel economy

There is no denying that electronic fuel injection significantly improves the engine’s fuel efficiency to a great extent. Now that you have understood some of the important pros and cons of both EFI and carburetor, you know what to look for when you are buying an ATV. 

An electronic fuel injection system is good on several levels. You get to spend less money on gas, which is a great deal over the carburetor. Also, you don’t have to refill the fuel tank frequently. That way, you can save a trip or two in a day. Moreover, because of the unmatched ability to meet the demand of the driver and the emission regulations, it is always good to have an EFI system. 

Electronic fuel injection provides fewer emissions, versatility, and more power. Unless you like experimenting with carburetors, the advantages of a powerful system that curtail emissions can’t be ignored. Although carburetors are favored by enthusiasts, an EFI system isn’t something that you can overlook when it comes to having great performance. 

Conclusion

Almost every ATV that you find around is fuel injected because of its ability to adapt to air-fuel mixture. The electronic fuel injection system is far more superior compared to the carburetors. And, that’s the reason why you shouldn’t overlook it when buying an ATV.