Gumout 800001363 High Mileage Fuel Injector Cleaner - 6 oz.

The Gumout Fuel System Cleaner is fantastic! I’ve used it in my car, and it really made a noticeable difference in engine performance. The cleaner helps reduce engine knocking and improves fuel efficiency. It’s easy to use and the 6-pack offers great value, ensuring I always have some on hand for regular maintenance. Definitely a must-have for anyone looking to keep their vehicle running smoothly. Highly recommend!

Gumout makes good products

I found a video by Scotty Kilmer, a popular YouTube automotive expert, where he tested this product on a car to see how well it works. In the video, he used a borescope to check the engine’s cylinders before and after running two full tanks of fuel treated with the product. The results were impressive: the cylinders looked much cleaner after using the additive, with clear reductions in carbon deposits and dirt. Scotty pointed out that this was an independent test, done without any sponsorship or outside influence, which meant the results were fair. Based on his findings and the manufacturer’s directions, I chose to use the product as instructed, adding it to my fuel tank to keep my engine running well and clean. The simple application and noticeable results make it a great addition to my vehicle maintenance routine, especially for keeping the fuel system and cylinders in good shape. I use it every 2 months (approx 3-4k miles) and my acceration and idle are like it came out of the factory.

Used one bottle during a fill-up and noticed slightly smoother engine performance. It’s hard to measure long-term effects, but for the price and quantity, it’s a great value. Easy to use and well-packaged. I’ll continue using it as part of my regular maintenance routine. One star off just because results aren’t dramatic.

Did a great job on a 35 year old injection system, got it sounding good and restored quite a bit of the fuel mileage percentage.

Why did you pick this product vs others?:I've had great luck with Gumout Multi-system Tune-up, so I figured I'd also give this a try. It seems to work just as well. The difference before/after is not subtle. The engine seemed to pull effortlessly and very smoothly. Much more low end torque. And this was on 87 octane. I made sure total gas in the tank was about 15 gallons, so, somewhat below the maximum Gumout suggests, i.e. a concentration somewhat on the high side. Very very impressed. Will definitely buy again.

Used all FairPlay good Price will ordert more soon

My engine (2013 6-cylinder Mazda) appeared to gain better performance as I used it.