How Fuel Injector Cleaner Works

If you've recently been told you have a dirty fuel injector, then it only makes sense that you'd want to know more about fuel injector cleaner. However, knowing you're interested in addressing a potential issue with your fuel injector before it has a chance to escalate is one thing. Actually understanding the many products out there on the market is another, so it's only natural to have questions. For one thing, does fuel injector cleaner really work? If it does, how well does it work, and how often should you use it to keep your vehicle in good working order? Here's a closer look at everything you need to know about fuel injector cleaner in order to make a wise decision.

What Does Fuel Cleaner Clean?

Most modern vehicles use fuel injection, a system which uses precision injectors to supply enough gas for the ideal fuel/air ratio in an internal combustion engine. Any issues with a fuel injector can reduce the amount of fuel in the ratio and reduce the efficiency of your vehicle. Over time, a completely clogged fuel cleaner may prevent your vehicle from starting.

Buildups of various contaminants can occur throughout your vehicle. From your fuel injectors and combustion chamber to your exhaust system, a buildup of by-products is difficult to remove and harmful to the overall fuel economy and performance of your vehicle.

What Contaminants Build up in a Fuel System?

Newer vehicles are designed to prevent buildup of contaminants from gasoline. Older vehicles are susceptible to buildup and clogs from two main contaminants: ethanol and carbon. Ethanol, also known as ethyl alcohol, is an additive used in gasoline. Ethanol is derived from corn, so it’s a renewable fuel source that can boost octane. Early introduction of ethanol was designed to reduce emissions and improve overall air quality, but modern engines no longer need this aspect of ethanol.

Instead, ethanol is typically used as a cost-saving measure. The alcohol in ethanol is corrosive, so it can oxidize and emulsify into a by-product that isn’t combustible. Over time, this buildup can clog your intake valves and fuel injectors.

Carbon is another by-product of your engine’s normal operations. Even more than ethanol, carbon deposits can reduce efficiency and clog up your system. Carbon is naturally found in gasoline, but your engine isn’t able to burn 100% of the carbon while it’s running. Most of these carbon deposits make their way out your exhaust system. Some, unfortunately, can remain in your fuel injection system and prevent proper fuel injection.

How Can You Tell Whether Your Fuel Injector Is Dirty?

Your fuel injector doesn't necessarily get dirty so much as it can simply become clogged at some point. (No literal dirt or outside debris should be making its way into your engine.) Fuel contains various elements that can leave deposits behind as they pass through the parts of your engine. These deposits build up over time in your fuel system, eventually making it less efficient and affecting your car's overall performance as a result. How can you know for sure that you're dealing with a clogged fuel injector and not some other issue? Evaluate your vehicle for the following signs that it's time for a cleaning.

  • Your engine has been misfiring, stuttering, lurching, or choking. When fuel injectors become clogged, their ability to properly mix the fuel with air can be affected.
  • Your engine stalls or idles in a way that sounds or feels "rough". This is caused by low RPM due to a fuel supply that isn't flowing smoothly or efficiently.
  • Your engine just plain hasn't been feeling as powerful as it normally does. Anything that gets in the way of proper combustion, up to and including clogged fuel injectors, can result in a noticeable loss of engine power.
  • Your gas consumption is on the rise. This is also due to combustion issues that keep fuel from being utilized as well as it normally would be.
  • Your vehicle has been failing emission tests. Uneven fuel combustion caused by clogged injectors can easily result in enough harmful emissions for a failing result.

What's the purpose of fuel injector cleaner? It removes the residue that's clogging up the works so that your car can get back to being reliable and running smoothly again. The more of the above signs you've been noticing in your vehicle's performance lately, the more likely it is that your fuel injector could use a little attention. Keep in mind that this is something that's eventually necessary for every vehicle, as all fuel injectors become clogged sooner or later.

What Does Fuel Injector Cleaner Do?

The great majority of the cleaners on the market contain chemicals (like polybutene amine, or PBA, to name just one example) that are specially formulated to break down any deposit build-up.

However, it's important to remember that such cleaners work best when used regularly to not only break up existing deposits, but reduce the likelihood of new deposits forming. How often you should clean your own fuel injector depends on what you drive. Some manufacturers consider a cleaning every 30,000 miles or so to be adequate, but others may suggest one every 15,000 miles or thereabouts instead. Here's a brief rundown of what most products on the market do for your system:

  • Rid both the nozzles of your fuel injector and your engine's combustion chamber of troublesome carbon deposits.
  • Enhances your vehicle's ability to burn fuel efficiently, meaning you'll likely get better gas mileage and enjoy a smoother overall driving experience.
  • Keeps your entire fuel system adequately lubricated, minimizing friction and slowing the speed of future deposit buildup.

As with other parts of your regular vehicle maintenance routine, regularly cleaning your fuel injector will extend the life of your engine and ensure it runs better overall.

How Often Do Fuel Injectors Need to be Cleaned?

Some individuals choose to use cleaning products with every tank of fuel, while others believe that fuel injection cleaning isn’t necessary. If you’re looking for a general time frame, a good place to start is using fuel system cleaner every 3,000 miles.

Of course, many factors can affect this timeline. If you are planning on long-term storage for your vehicle, clean the fuel injection system first. A resting vehicle is more likely to experience carbon buildup and emulsifying ethanol.

If you drive an older vehicle, you may want to consider cleaning your fuel system more frequently. Older vehicles don’t operate as efficiently and aren’t designed to avoid ethanol buildup, so there’s a greater risk of a clogged fuel system.

How Do I Use a Fuel Cleaner?

If your engine is stuttering, vibrating, misfiring or your check engine light turns on, it may be time to use a fuel cleaner. So, how do you use fuel cleaner? Here are the basic steps to effectively using a fuel injector cleaner:

How to Use Fuel Cleaner

1

Choose Your Cleaner

Purchase your favorite brand of fuel cleaner. If you don't have a preferred brand, do some research on what cleaners are often used on your make and model of car.

2

Start with an Empty Tank

For optimal use, be sure your fuel tank is near empty.

3

Read the Instructions

Follow the instructions that came with your fuel cleaning bottle. Add the correct amount of cleaner directly into your fuel tank. You can check your service manual to determine the size of your fuel tank.

4

Top Off

Top off your fuel tank and idle your vehicle briefly before driving as normal.

These steps generally apply to most fuel cleaner products, but be sure you follow any directions specific to your brand of cleaning product. If your engine is still experiencing stuttering and misfiring, take your vehicle to your local mechanic for a complete inspection. This may be a sign that part of your fuel system is damaged.

What To Consider When Choosing a Fuel Injector Cleaner

Not all fuel injector cleaners are created equally. Some are going to be better fits for your needs than others, so it’s important to know what each option brings to the table. Here are a couple of tips to keep in mind as you evaluate your options.

  • Some products focus on cleaning buildup, while others are better for maintenance purposes. Many products do both. Always thoroughly read product packaging before buying to make sure it’s the best fit for your purposes.
  • Be realistic about what you can actually expect from a fuel injector cleaner. A very old vehicle that hasn’t been maintained over the years or a lemon with an engine that’s completely falling apart is likely beyond the help of even the best cleaner.

At the end of the day, keeping your fuel injectors clean, clear, and functioning properly is all about staying diligent about ongoing maintenance. As with many potential engine problems, it’s always much easier to simply stay on top of ongoing concerns than it is to try to reverse a huge problem later on. Your engine (and your wallet) will definitely thank you for it.


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