The 10 Best Fuel System Cleaners

We spent 46 hours on research, videography, and editing, to review the top choices for this wiki. Having a little car trouble? Perhaps one of these fuel system cleaners can help. Good for solving an existing problem or as a regular preventative, they are designed to flush out crud and deposits in your injector system; eliminate engine knocking, pinging, and run-on in older cars; improve fuel economy; eliminate rough idling; reduce spark plug fouling; and reduce harmful emissions. When users buy our independently chosen editorial picks, we may earn commissions to support our work.

10. Lucas Oil 10013 Lubricant

Lucas Oil 10013 Lubricant neutralizes the harmful effects of low sulfur diesel, and it is safe to keep in a motor home in hot climates. It can help decades-old cars feel new again, and increases the miles per gallon in fuel-guzzling pickup trucks within a few tanks.

  • Improves cold starts
  • Increases the life of your pumps
  • You need to use a lot to see results

Brand Lucas
Model LUC10013
Weight 7.6 pounds
Rating 3.9 / 5.0

9. STP 17437 Ultra

STP 17437 Ultra is a powerful, five-in-one product that contains corrosion inhibitors, high-performance detergents that optimize your engine, and ethanol deposit inhibitors that not only clean, but also prevent rust. It goes in your oil and stays effective for 4,000 miles.

  • Consistent across all car types
  • Especially useful on hybrids
  • May take a while to see effects

Brand STP
Model 17437
Weight 11.2 ounces
Rating 3.5 / 5.0

8. Star Brite Star Tron

Star Brite Star Tron can help rejuvenate old, sub-spec fuel and is particularly good at making small engines easier to start. It also breaks down excess water and sludge to sub-micron size, allowing it to be safely burned away during normal engine operation.

  • Greatly reduces fuel emissions
  • Measurement scale on the bottle
  • Cap may leak a little

Brand Star Brite Star Tron
Model pending
Weight pending
Rating 4.1 / 5.0

7. Sta-Bil 360 Performance

Sta-Bil 360 Performance works on your intake system, throttle plate, carb, and fuel system to effectively prevent gum, soot and varnish from collecting in the nooks and crannies of your engine. Plus, it’s very simple to use, even for beginning auto DIYers.

  • Vapor tech protects above fuel line
  • Great for ethanol-blended gas
  • More preventative than restorative

Model 22275
Weight 1.9 pounds
Rating 3.8 / 5.0

6. Lucas Oil 10512 Deep Clean

Lucas Oil 10512 Deep Clean does an impressive job of clearing combustion chambers and eliminating engine knocking, pinging, and run-on in older cars. It coats all metal surfaces effectively, but it can only be used on gasoline engines, not diesel.

  • Helps to reduce stalling
  • Can prevent fuel gauge malfunction
  • Not safe to store in hot climates

Brand Lucas Oil
Model 10512
Weight 15.2 ounces
Rating 4.3 / 5.0

5. Red Line 60103 Complete

Red Line 60103 Complete is very effective in high oil-consumption cars, removing nasty coats of goop from the PCV valve and intake manifold. Plus, it reduces the need for octane by up to two points and contains a high concentration of polyether amines.

  • Tapered bottle for easy storage
  • Eliminates rough idling
  • Doesn’t improve mileage that much

Brand Red Line Oil
Model RED60103
Weight 10.4 ounces
Rating 4.0 / 5.0

4. Lubegard 77012 Booster

If you need a fast and affordable way to rejuvenate your fuel system, grab a canister of Lubegard 77012 Booster. This portable product contains a proprietary additive that provides lubrication to fuel pumps and injectors, and prevents bacteria growth inside diesel tanks.

  • Prolongs fuel life in storage
  • Greatly restores injector flow
  • Makes spark plugs look brand new

Brand Lubegard
Model 77012
Weight 1.1 pounds
Rating 4.6 / 5.0

3. Chevron 65740-CASE Techron

Chevron 65740-CASE Techron will help restore operation of your fuel gauge sensor and reverse lost acceleration, as well as reduce spark plug fouling. It’s also a favorite among mechanical and chemical engineers, who remark that it leaves fuel injectors sparkling clean.

  • A little goes a long way
  • Wipes out corn fuel tarnish
  • Best for very dirty engines

Brand Chevron
Model 65740-6PK
Weight 5.5 pounds
Rating 4.7 / 5.0

2. BG 44K

The BG 44K comes with four cans, each of which can treat up to 20 gallons of gasoline, and is compatible with all fuel system materials, alcohol-blended fuels, and common fuel additives. It’s very effective at eliminating hesitations on acceleration.

  • Smooths engine running
  • Good value for price
  • Also great for lawnmowers

Brand BG
Model pending
Weight 3.1 pounds
Rating 4.6 / 5.0

1. Royal Purple 11723 Max-Clean

This Royal Purple 11723 Max-Clean is a best-selling solution that can effectively reduce hydrocarbon, NOx and CO emissions for all environmentally-conscious drivers out there. It can be used in both 4-cycle and 2-cycle engines, and won’t harm delicate catalytic converters.

  • One can treats up to 20 gallons
  • Epa and carb compliant
  • Boosts fuel mileage noticeably

Brand Royal Purple
Model 11722
Weight 8.7 pounds
Rating 4.7 / 5.0

Money At Both Ends

There’s a long, rich history of commercial rackets in the US. The manufacturers of fast food and tobacco products, for example, are often owned by the same corporations that own the pharmaceutical companies who sell you the treatments for all the sickness their poisons cause. These are masked men who steal your purse one minute, disappear around the corner, take the mask off, and reappear offering to help you find the man who stole your purse–for a fee, of course.

The same sad truth applies to our oil-producing overlords, who behave remarkably like drug dealers. If you dealt heroin on a large scale, you’d likely want to get the purest stuff you could find. Think of it like oil that’s been extracted and cleaned, but not yet turned into gasoline. You could take one kilogram of that pure heroin and sell it as is on American streets for about $130,000.

Or, you could cut it with different chemicals, a little vitamin C, a little baking powder, maybe some Ajax–whatever’s lying around. As long as you don’t reduce the potency so much that the side effects of the additives outweigh the natural effects of the drug, you can turn one kilogram into two kilograms, effectively doubling your profits.

You buy gasoline by the gallon, but gasoline isn’t just refined oil anymore. It’s loaded with detergents and other additives, and about 10% of all your gasoline is actually ethanol. Ethanol is an alcohol derived from corn that the government and gas companies collude to include in your gas mainly to offset overproduction of corn resulting from imbalanced farm subsidies.

Ethanol boosts the octane level of your gas, it pays out double to industrial agriculture companies for overproducing corn, and it gives the oil companies a 10% bump in profits (your tax dollars pay for the ethanol in your gas long before you swipe your card at the pump). Worst of all, though, is that it’s terrible for your vehicle, causing a gross accumulation of non-combustible deposits in your entire fuel system. Even without the ethanol, you’d see a build-up of gunk over the years, but that corn juice exacerbates the problem significantly.

Cleaning Up Your Decision

Nowhere are these non-combustible components more damaging than in your fuel injector. The fuel injector sprays a fine mist of gasoline into you air intake to create the highly explosive mixture that powers your engine. If your injector is clogged with debris like an old shower head pumping hard water, the quality of your combustion plummets.

A gunky injector results in less power, poor idling, impacted fuel mileage, and dirtier emissions. The detergents present in the gasoline you purchase are intended to reduce the build-up of gunk in your fuel system, but, given the presence of the ethanol, they can only do so much. Fuel system cleaners can take care of the rest.

That gunk is mostly made up of carbon built up from those dirtier ingredients’ exposure to numerous heat cycles in the engine. Fuel system cleaners contain detergents, most often a detergent called polyetheramine, or PEA, that specifically target carbon deposits. Those deposits can cleanly pass through your exhaust system in the natural combustion process. It’s a lot like using laser to break up kidney stones into more comfortably passable sizes.

To deliver the cleaner into your fuel system, most products pour right into your gas tank. These tend to work best when added just before a fill-up, right there at the pump. As you consume that tank of gasoline, the cleaner passes consistently through your fuel injector, scrubbing away at any built-up deposits throughout. These systems have the injector as their primary point of focus, leaving some other areas of the fuel system less treated.

The other delivery method, comprised of much the same solution, comes pressurized in a can with a long, thin hose attached. The other end of that hose enters your vehicle’s throttle body through the fresh intake hose. You’ll need an assistant to actively use this system, as it requires another person to start the car and, depending on its idling point, keep the engine at 500-1,000 RPM. These solutions also often include lubricants to keep additional gunk from building up over time.

Some systems come with a combination of gas tank-based fuel injector cleaners and engine system cleaners and lubricants, and the latter are certainly the more intensive treatments. If you’re a novice when it comes to your vehicle, or you’re a consummate loner who doesn’t have anybody you can ask for help, you want a solution that will requite as little mechanical knowledge or physical assistance as possible, so keep away from the more complicated cleaner systems. If you have even a modicum of competence in the garage, the more comprehensive systems should be a breeze.

Refined To The Point Of Contamination

It took nearly 200 years from the conception of the internal combustion engine for anyone to actually build one that worked. In the 1860s, a French scientist named Alphonse Beau de Rochas patented a design for a four-stroke engine, but he never completed its build.

In 1878, Nikolaus A Otto completed the build of a four-stroke engine that actually ran. It’s a great name for an engine builder, even if the term ‘Otto-mobile’ didn’t catch on. Still, his engine and the two-stroke engines that came out in that same year were either too big, too slow, or both. They weren’t commercially viable products.

1889 saw the introduction of a four-stroke, carburetor-regulated engine with its cylinders aligned in the shape of a V. This engine came at the hands of Gottlieb Daimler engineering out of Germany. The developments from this point forward led to the industrial advancements on the assembly line in America and to the explosion of the automobile industry worldwide.

In the years since the, gasoline itself has become increasingly pure, as methods for refining oil gained more and more scientific precision. In the last couple of decades, however, we’ve seen the introduction of new chemical agents and alcohols sold to us as solutions to problems that weren’t there, which create new problems for our engines.