Product works very well. we use it on several company vans as well as small engines that have never had any deposits at all when changing spark plugs (even after one unit was over 1 year on same plugs, they still looked new). Also keeps turbo GDI's nice and clean (still need professional cleaning, but half as often.

Gumout All-In-One Diesel Complete Fuel System Cleaner is best used after every oil change as a part of your vehicle's maintenance schedule. If you live in below freezing temperatures, you may wish to use it more frequently to avoid fuel gelling issues.

Your engine to fight ethanol. And water corrosion. Plus it stabilizes fuel and oil in simple use just add one ounce per gallon of fuel.

Is it worth adding to your gas tank? In short, when used regularly, fuel cleaners work. They can help remove harmful deposits, prevent new deposits from forming, and enhance vehicle performance. Fuel additives can improve gas mileage, reduce long-term maintenance costs, and they're affordable.

Comparison of best fuel injector cleaners

If you use a Gumout fuel additive when your tank is full, it will just take longer for the additive to mix thoroughly with your fuel.

Fuel system cleaner is mostly alcohol. Putting in too much will give you a higher octane rating and less MPG and less power.

Directions for Use​ Add entire bottle to nearly empty gasoline tank, ideally at time of oil change. Refill tank with up to 25 gallons of gasoline. For best results, do not refill tank until near empty. Repeat every 3,000 miles.

When should you use a fuel injection cleaner? A good rule is each time you change your oil. You can add a fuel system cleaner at regular intervals to help prevent mechanical issues, or if you notice problems with rough idling or irregular combustion.

Here are a few signs that there might be something wrong with your fuel injectors.

• THE ENGINE MISFIRES. Dirty fuel injectors may cause your vehicle's engine to misfire.
• IDLING GETS ROUGH.
• YOUR GAS MILEAGE TANKS.
• THE RPM NEEDLE STARTS TO DANCE.
• YOUR CAR WON'T START.
• THE CHECK ENGINE LIGHT GOES ON.
• YOU SPRING A FUEL LEAK.

Although most fuel injector cleaners begin working immediately, it takes time before the improvements become noticeable. Before the cleaners start working effectively, the vehicle should travel several hundred miles and burn a good portion of a full fuel tank.

The K&N Performance+ Fuel System Cleaner is the #1 best-selling fuel system cleaner on Amazon. It cleans the entire fuel system and helps restore lost engine power, acceleration and throttle response. It's safe to use for all direct injected and fuel-injected engines.