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Fuel injectors are the bridge between a full tank of gas, and your engine utilizing that gas. As a result, you can imagine they’re critically used every time you start the car up. Cleaning them properly keeps your MPG accurate, reduces noise in the engine block, and eliminates motor chatter, while slightly reducing your emission output. Having the right cleaner can cut down on maintenance frequency, and improve your vehicle’s overall performance. We’re here to help you pick the best fuel injector cleaner on the market.
The Best Fuel Injector Cleaner
Another all-in-one product that does the job of three different items. Chevron’s name is synonymous with superior power, and their fuel cleaner showcases that. Use this on any automobile you have, including the engine on your boat, your RV – anything at all. This restores lost power and acceleration.
Replenish your lost fuel economy and eliminatie horrible firing issues, such as loud, rumbling idling, hesitation, and problems with your spark plugs on startup. If you’re in a rapid-changing environment, this protect your engine from negative cold startups, makes them easier, and lasts for up to one year in your system.
Works on your entire fuel intake system, not just your injectors
Designed to work on ATVs, dirt bikes, and boat engines as well
Reduces idling issues and eliminates spark plug fouling
- Weight1 pounds
Red Line is the king of oil and fuel additives, but they didn’t stop there. They’re all about optimizing your engine’s performance, even if that means an in-depth cleansing. Red Line’s patented formula gives most users 100% efficiency after the first use.
You kill two birds with one stone – Red Line includes synthetic upper cylinder lubricant, performing maintenance on your vehicle while you’re performing maintenance on your vehicle; it’s a win-win. Available in a singular 15-ounce pack, or in a bulk of 12 for a rough 27% savings (generally, that would be a 20-year supply).
In most cases, 100% efficiency after the first clean
Contains complete upper cylinder lubricant (synthetic)
Two uses per bottle (use the full bottle if your vehicle has been neglected)
- BrandRed Line Oil
- Weight10.4 ounces
Liqui Moly does far more for your engine than your standard injector cleaner. If you’re noticing issues on startup, such as rapid clicking or stalling, you’ll be able to see your problems disappear. You get a better throttle response, as well as smoother idling (minimal vibration and unwanted “chatter” from the engine).
Attractively priced and in a 300ml bottle, Liqui Moly’s solution comes as a blessing for those with older vehicles/engines. Optimize your performance – those fuel injectors have gone through their paces, and it’s time to clean them up. You’ll notice immediate performance; can be used as a fuel additive afterwards.
Thoroughly cleans combustion chamber
Eliminates issues that occur on startup
Much smoother idling after use
- BrandLiqui Moly
- Weight20 pounds
When you don’t have time to dissect your fuel injectors, you want a cleaner that can also be added to your fuel tank. STP works either way, and is designed to compliment capless gas systems. Sediment and sludge doesn’t stand a chance.
This formula increases your oil pressure while adding to your city and highway fuel economy, in most cases, it can optimize performance up to 3-4MPG, and is perfect for any make/model car, no matter what. STP offers their fantastic solution in a twin pack; each plastic bottle is designed for easy pour.
Perfectly compatible with capless gasoline systems
Works hard to remove sediment deposits and sludge around seals
Powerful enough to be used as a fuel additive and still remove clogs
- Weight11.2 ounces
Lucas is the leader for fuel and oil additives, and with this formula, they give us a solution that perfectly cleans your engine block while running its course through your system. Increase your fuel economy with this value-size, one-gallon fuel treatment in an easy to pour bottle. Lubricate your system while you clean it.
If your injectors are old, or you just want to prevent them from taking any more damage, Lucas’ oil is your go-to. This one was tricky to mark; it’s an all-in-one product that gives you the benefits of a fuel additive, the power of an oil additive, and cleans your fuel injectors like a professional. Reduces sediment and sludge, available for 12% off in large bulk deal (4 gallon purchase).
Increases life expectancy on pumps + injectors
Cleans fuel intake system while lubricating
Increases power while also increasing fuel economy
- Weight8 pounds
If you’ve never used Royal Purple on your car, then you need to rethink some things. Royal Purple has been American’s go-to for years for it’s no-BS approach; you get results, and nothing less. Completely eliminate stalling and hesitation issues while adding percentage points back onto your fuel economy.
This stays in your car’s system for some time after use, upholding high performance standards. Increase your horsepower while knocking down your harmful emissions by up to 18%. Available in bulk deals with up to 15% savings on total cost (12-year supply on average).
Prevents hesitation and stalling
Upholds optimal performance long after use
Improves your fuel economy, on average up to 3% or more
- BrandRoyal Purple
- Weight1.25 pounds
Big things come in small packages – for seriously potent effects, Gumout rises to the occasion. This fuel injector cleaner continuously lubricates your engine’s fuel system for months after use, reducing the rate that sediment and stubborn carbon deposits form.
Reduce emissions while maximizing your fuel economy, while providing superior protection for multiple components of your engine block. This takes your injectors from plugged/clogged, to brand new, right off the assembly line (as far as performance goes). Gumout is the ultimate preventative measure to elongate the life expectancy of your injectors.
The answer to supercharged and turbocharged vehicle issues
Removes stubborn carbon deposits (on engines over 75,000 miles)
Lubricates effectively to reduce sedimentary deposit buildup rate
- Weight0.16 ounces
If you’re using a variety of fuel treatments, additives or other products in your car and you’re wondering whether the fuel system cleaner you wish to add will adversely react with these chemicals, there’s no need to worry as long as you get the BG 44K Fuel System Cleaner. Its unique formulation allows it to be used with common fuel additive, alcohol-blended fuels, and other fuel system materials so you get the best of both worlds.
The 44K easily cleans not only your fuel injectors but also your combustion chambers and the valves to your car’s engine, allowing it to breathe more efficiently and drawing the much needed power from your fuel system to drive your wheels. Avid car enthusiasts can surely attest to the 44K’s ability to transform their car’s fuel system into a highly efficient mechanism, saving you gas, and giving you the power you need from your engine.
Compatible with a variety of fuel products and additives
Improves gas mileage, power output, and combustion quality
11-oz can good for 20 gallons of fuel
- Weight11.2 oz
There are no concrete guidelines as to when you should keep on putting fuel cleaners into your system, often depending on the current status of your fuel injectors. The good thing about the Techron fuel injector cleaner is that you can safely add it to your fuel after every 1,000 miles. Chevron also says that you can put it into your car’s system as often as needed to help make sure that all the nasty deposits that build up over time will be effectively removed.
Of course, discretion should always be exercised in such cases, even though Techron is especially formulated to be ideal for both carbureted and fuel injected systems. It won’t affect your car’s catalytic converter or even oxygen sensor if ever it comes with one or both of these devices. The only downside is that the Techron cannot be used on 2-stroke air-cooled engines so you’ve got to really check your engine to determine its compatibility.
Formulated for fuel-injected or carbureted engines
Safe for oxygen sensors and catalytic converters
Every 1,000 miles recommended use
- Weight20 oz
If you’re looking to reduce if not eliminate the nasty knock coming from under your hood, Motorcraft has the answer. Featuring a unique blend of engine- and fuel- friendly chemicals, the PM6 comes with a high-strength formulation that can make your valve deposit worries a thing of the past. It’s especially designed for the reduction of engine knock, improving your gas mileage in the process.
It may not have the big-name brand on its label, but the PM6 is surely gaining ground as one of the best fuel injector cleaners of the modern times. Even fans of more popular brands cannot help but be impressed by the PM6’s overall fuel system cleaning performance. Now all you need is to try and experience it for yourself what others have discovered as a true fuel system cleaner.
High-strength fuel cleaner formulation
Eliminates deposits from intake valves
Reduces engine knock
- Weight12 oz
Fuel Injectors Buying Guide & FAQ
Maintain your fuel injectors, and you’ll upkeep optimal performance. As such a vital component to your engine, you need to know every possible issue that can pop up, and how to properly clean them to ensure there’s no repeat mistakes. Here are some of your most frequently asked questions about cleaning your fuel injectors.
What do I Need to Clean My Injectors?
You need the following:
- The best Fuel injector cleaner for your vehicle
- Fuel pressure gauge
- Hose for attachment to fuel injector and rail
Nothing else is needed to do this on your own, though this is assuming you have basic tools on standby in case you encounter any other issues while attending to the fuel injectors. This is the perfect time to run a visual diagnostic on your vehicle and make a shortlist of maintenance tasks you need to complete, so you won’t be cleaning your injectors for no reason.
When Should I Use a Fuel Injector Cleaner?
In most cases, you’ll see a lot of debates stating that you don’t need a injector cleaner or kit unless you encounter issues. In truth, preventative measures can offset 99% of all issues, so tending to this on a routine basis is strongly suggested.
You can expect to do a deep cleaning of your fuel injectors once a year, up to 30,000 miles. Anything over that, and it’s recommended to clean them again.
How do I Know if I Have a Clogged Fuel Injector?
There are a few ways to tell; let’s go over them.
- Lowered Fuel Economy
If you have a digital meter in your car that displays your current MPG, pay attention to it at least once per ride. If you’re usually travelling the same routes, such as heading to and from work each day, you’ll get a firm understanding of what your MPG should be, both in and out of traffic, on and off of highway. When you notice that there’s a significant decrease, such as 3-4 less MPG on your average, it could be an indicator of fuel economy problems.
This isn’t exclusive to fuel injector issues. Lower gas mileage can be a result of spark plug misfiring, bad air filters, incorrect tire pressure, and more. You shouldn’t immediately assume that your fuel injectors are the problem, but you also shouldn’t rule it out.
- Forcing Your Engine
If you can feel that your engine doesn’t want to start, that you’re having issues every time you hop in the driver’s seat, you could have clogged injectors. Your injectors release a mist of gasoline, and when one or more aren’t firing properly, it gives unbalanced results. You should be able to hop in the car, twist the key, and be on your way with no worry.
- Not Firing on All Cylinders
That phrase got its name from this issue; when your cylinders aren’t firing properly, you can hear it. Whether you have 4, 6, or 8 cylinders, you’ll be able to hear it. If you’ve recently opened up your hood and can visibly see gasoline on your spark plugs, you definitely have a clogged fuel injector.
How to Use a Fuel Injector Cleaner in 7 Easy Steps
After reviewing the layout of your specific make and model engine in your user’s manual, you should get everything ready and prepare to get your hands dirty. It’s recommended to wear gloves during this to avoid gasoline/oil absorption through your skin.
Start by disconnecting the fuel pump from the fuel injectors. This will require you to use a U-tube to ensure that gasoline returns to the tank, or the fuel return line. Some vehicles will have a different way to go about this depending on your make and model.
- Disconnect the Pressure Regulator Vacuum Line
Normally, this is found slightly above your fuel injectors, though it will vary depending on your make and model. Be careful to keep the vacuum line perfectly intact upon removal, and lean it gently over the side of the hood.
Use that hose you have sitting by; connect it to the fuel pressure test port, and secure it tightly. Ensure there is no exposure to fuel of any kind by revisiting these steps and ensuring all parts are clear. Fuel injector cleaner is flammable; use caution.
- Remove Fuel Tank Cap
Simple portion of the process, just be certain to put it somewhere you won’t lose it.
- Turn the Car On
This is where is gets a little tricky. Turn your car on, but before you do this, be 100% certain that the fuel pump is off and then engage. The cleaner from your kit will begin to run through the engine. Within 5-10 minutes, the engine will shut down when the cleaner has run its course. After this point, remove the cleaner tube.
Now, reattach the fuel pump power supply, as well as the pressure regulator hose, and then, reapply your fuel cap.
- Quality Check
Turn your car back on to ensure the fuel injectors are reconnected and functioning properly. Drive it around the block for 5-15 minutes to really be certain. If you’re still noticing the same problems as before, and you know that your fuel injectors are clean as whistle, you may need to replace them.
Three Step Process for Less Invasive Use
If you’re not too keen under the hood, or you just want to give your car a little TLC, you can still use some formulas of fuel injector cleaners without having to dissect an area of your car that you’re not familiar with.
- Ensure Your Tank is Nearly Empty
You don’t want to dilute your solution in a full gas tank; ensuring that you have one gallon of gas or less is crucial to using this method.
- Use the Appropriate Amount of Injector Cleaner
This is going to depend on the capacity of your gas tank. This is a good time to grab your owner’s manual and give it a read. Carefully read the instructions for the cleaner you’ve chosen, and match the recommended amount to the size of your tank.
Put the contents of your fuel injector cleaner of choice into the tank, add your regular fuel (this will push the cleaner through your injectors upon next startup), and you’re good to go.
Can Fuel Additives Help my Injectors?
Fuel additives can be helpful for numerous reasons, but if you’re storing your car for a long period of time - especially if you’re a proud owner of a vintage car that rarely comes out from under the tarp - you’ll want fuel injector additives.
These prolong the life expectancy of your fuel/oil, so you won’t have to worry about buildup or long-term corrosion. Fuel additives help keep your injectors lubricated and ready to go when you are.
Benefits of Clean, Fresh Fuel Injectors
Controlling Fuel Consumption - As mentioned before, you can notice a decrease in MPG if your fuel injectors aren’t clean. Doing a quick bit of math tells you that, if you drive around with your fuel injectors coated in buildup and grime, an everyday commuter could see a savings of $52.50 per year, or 21 gallons of gas.
Decreased Metal-to-metal Friction - Your engine is a contraption of moving metal parts, each specifically lubricated to work with one another. Except, when buildup occurs, your engine ends up getting pretty nasty, and friction slowly chips away the working parts of your motor.
Decreased Emissions - Under the same rule of increasing your fuel economy, you’ll produce less harmful emissions. It’s not a huge impact, but an impact nonetheless.
Q: Can Fuel Injector Cleaners Fix Leaks?
A: On their own, they cannot - if you find out you have a main line leak, you’ll have to have a professional mechanic patch it up, or use oil additives (provided the leak is insignificant enough). The best fuel injector cleaners can help you locate a leak; during the cleaning process, when pressure builds and you’re already under the hood, you’ll be able to tell if there’s a leak, (especially if there’s gasoline on your spark plugs).
Q: Do Fuel Injector Cleaners Help Other Engine Functions?
A: While the primary focus is on your fuel injectors, they do help with a once-over for other parts of your engine. If you take a moment and use a rag, these cleaners can eliminate grime built-up around your gas cap (which you will have to remove during the cleaning process). They’re also about more than just cleaning the section where your injectors propel mist.
We would all like to believe that all fuel additives, which most of us use, do the trick in eliminating sediment buildup and slow down the production of grime. While they do help, it’s a fantasy to believe that they can do it all, and over long periods of time.
Fuel injector cleaner is able to cut through those stubborn chemical buildups and sludge in the engine. It’s not going to be a preventative measure for very long, but eliminating that residue from your engine and its moving parts can give you immediate benefits that would otherwise elude you.
Q: Are Fuel Injector Cleaners and Oil/Fuel Additives the Same Thing?
A: While some cleaners will have similar benefits of oil additives or fuel additives, they are not the same product. Additives are there to enhance your vehicle’s performance, while cleaners are simply optimizing the performance of your fuel by removing clogs from your internal parts. Think of them as two sides of the same coin - you want your additives to work properly, so you need clean injectors.
Q: After how many miles should fuel injectors be cleaned?
A: Everything actually depends on a variety of factors such as the age of your vehicle, the kind or types of fuel your engine uses, and the actual recommendation coming straight out of your vehicle’s owner’s manual.
As a general rule, the newer the car, the less frequent is the fuel injector cleaning. Conversely, the older the vehicle, the more frequent is the cleaning of the fuel injectors. One has to understand that as the engine burns fuel, deposits inadvertently build up inside the surfaces of the network of valves, tubes, and other contraptions in the vehicle’s fuel system. With the passing of time, more and more deposits typically build up and the engine also loses some of its efficiency in burning fuel. That being said, a newer vehicle will typically burn fuel at a slower rate compared to a vehicle with an older engine. Because engine efficiency is no longer optimal in older vehicles, they’ll need more frequent fuel injector cleaning.
High-octane fuels also tend to improve engine efficiency as well as power output, requiring sufficiently less cleaning of the fuel injectors. On the other hand, vehicles that run on low octane fuels may require more frequent cleaning.
Perhaps the best information on how many mils you should start cleaning your fuel injectors will be the one located in your owner’s manual. Different car manufacturers use different engine layouts and specifications that may play a role in the rate of deposit buildup. Generally, as the vehicle ages, there’s a commensurate increase in the frequency of cleaning.
Most car manufacturers recommend cleaning the fuel injectors after every 30,000 miles while others recommend after every 15,000 miles. Now this is typically for the more tedious aspect of cleaning your fuel injectors. But if you’re going to use the hassle-free method of simply pouring a the best fuel injector cleaner into your car’s fuel system, then everything actually depends on the purpose of the cleaning.
If the goal is to improve gas mileage and for general maintenance, lower doses of an appropriate cleaner placed with every other full tank is recommended. If your purpose is to solve minor issues and to provide a deeper clean in your fuel injectors, a higher dose of a stronger fuel injector cleaner can be added into your system every 3 to 6 months. If the goal is to address fuel injectors that are suspected of being clogged, you’ll need the largest dose of the strongest fuel injector cleaner to be added into your system once a year.
Q: What causes deposits and can they hurt my vehicle?
A: Deposits are nothing less than impurities present in fuel that can lead to a variety of problems. It can actually be likened to human blood that circulates throughout the body. Impurities in the blood can sometimes accumulate to dangerous levels that they can form plugs inside the walls of blood vessels, impeding efficient blood flow.
In like manner, deposits that build up over time can lead to a host of problems such as lower gas mileage, hard starts, poor acceleration, engine knock or ping, loss of power, and even increased emissions. The problem actually depends on the location of deposits within the car’s fuel system.
If it is located inside the injectors, you may have issues with efficient fuel delivery leading to engine misfires, hesitation, rough idling, increased hydrocarbon emissions, and very bad fuel economy. A very lean fuel mixture can also lead to an increased risk of detonation. These deposits generally build up a lot faster with more frequent drive cycles and shorter trips as deposits form usually after the engine has been shut off.
Deposits can also form inside the throttle bottle often secondary to fuel vapors that emanate from the intake manifold, leading to rough idling.
If the intake valves form deposits, there can be substantial loss of high-speed power or acceleration. These deposits usually result from normal products of combustion, although broken or leaking seals or valve guides can worsen or hasten the rate of deposit formation.
If the deposits form at the top of the pistons or even inside the combustion chamber, this can lead to a significant increase in compression ratio. This inadvertently increases the need for a much higher octane fuel. If the commensurate increase in fuel octane is not achieved, there is a strong chance that detonation of spark knock can occur. If this is allowed to continue, the piston rings, head gasket, and even the rod bearings can get severely damaged leading to costly repairs. As a compensatory mechanism, the knock sensor will send signals to the PCM to delay the timing of the spark. Sadly, this can lead to increased emissions and a definitely worse fuel consumption.
Similarly, combustion chamber deposits can lead to preignition problems that can seriously damage your engine. This is due to the formation of hot spots. What happens is that the hot spot delivers the unwanted spark to the fuel even before the actual spark is delivered by the spark plug. This results in a very steep increase in combustion pressure. Automotive experts say that preignition, given increased load and RPM, can burn a large gaping hole straight through the piston top.
In other words, the cleanliness and purity of your fuel needs to be ensured, otherwise these impurities can accumulate over time and bring you greater headaches than you could possibly ever imagine.
Q: If my mechanic has advised me to replace my fuel injectors, should I do it?
A: There really is no easy way to say this, but if it is your trusted mechanic telling you that you need to replace your fuel injectors, then maybe you should do it. However, it is often best to look at some of the signs of a failing fuel injector to help you have a fair idea of whether there really is a need to replace these important components of your car.
Engine knock or even detonation is almost always an indication of a failing fuel injection system. Rough engine performance as well as bucking and surging under different loads can also indicate a failing system. Poor performance, poor idle, increase fuel consumption, and increased smoke coming from your exhaust pipe are other signs. Issues with starting the engine and the engine not reaching its full RPM can also mean a bad fuel injector.
The point here is that don’t take your mechanic’s word for it. You’re the one driving your car on a daily basis. If you something off, then you can consult your manual as to the most likely cause of the problem or problems you’re experiencing. If everything points out to a failing fuel injector, then you can have it replaced.
Q: How do you properly store fuel injectors?
A: Fuel injectors, regardless of type, have only one common enemy – corrosion. This is because the internal components of fuel injectors are made from a variety of steel alloys. When exposed to the elements these can easily oxidize or rust. As soon as the fuel left inside the injectors dries out, the deposits that have built up inside can actually harden. This can lead to the pintle sticking to the injector’s seat. If this happens, you’ve got a very expensive piece of junk – inoperable. It may still operate, but what you’ll get is a leaky injector.
As such, if you do decide to take out your injectors with the hope of putting them back in after some time, you need to store them properly. This can be done by removing any dirt or debris that is present both inside and outside the injectors. Spray all surfaces with the appropriate lubricant before putting these in a sealed container or plastic bag. Store this someplace where it’s cool and dry.
Q: What are the inner components of a fuel injector?
A: Your fuel injector is a work of art. It is composed of a variety of components that work together to deliver very precise amounts of fuel into your engine.
Located near the top of the fuel injector near the fuel rail is the fuel filter basket which effectively traps larger particles present in fuel from passing through and clogging the injector’s pintle and seat. The injector body holds the different internal components of the injector together. The coil winding is what pulls the injector pintle up and away from the seat.
The pintle is like the gate valve of the fuel injector. When lifted by the coil winding, it exposes a gap between it and the seat. This gap is where fuel passes through. Now, do understand that the pintle doesn’t really move that much – only by a few thousandths of an inch. The seat is where the pintle rests when not raised by the coil winding. It forms a seal around the pintle so that fuel will not pass through. Together the pintle and seat are the fuel injector’s core elements as they determine the rate of flow of fuel as well as the spray pattern of the fuel.
Lastly, there’s the pintle cap which holds an O-ring, forming a seal and protecting the rest of the fuel injector from heat generated by the engine.