STP Ultra 5-in-1 Fuel System Cleaner and Fuel Stabilizer (20 fluid ounces)

[This review was collected as part of a promotion.] I recently tried the STP Ultra 5-in-1 Fuel System Cleaner on my high-mileage vehicle, and the difference was noticeable almost immediately. After adding it to a full tank, I experienced smoother acceleration, better fuel efficiency, and a quieter engine. The product is easy to use—just pour it into a gas tank that's at least half full. It's designed to treat up to 26 gallons and is recommended for use every oil change or 4,000 miles. For anyone looking to give their fuel system a serious clean, I highly recommend this product.

[This review was collected as part of a promotion.] My husband used this in our 2013 suv. He said he noticed an immediate boost to the vehicles fuel economy. Was easy to read instructions and add to fuel tank. It has the typical injector cleaner smell. It was a good value for the money. He said he would buy again and use in our other cars.

[This review was collected as part of a promotion.] STP Ultra Fuel system cleaner works great. I add it to my sons 2010 Ford fusion, and it keeps it running like a champ. We add it to the tank before adding gas. This product deep cleans the entire fueling system and fights against engine friction.

[This review was collected as part of a promotion.] One the application into the gas tank isn't great. I got 93 percent of the product into the gas tank iwith around 7 percent spilling out and having to clean up on the floor. After going through a tank of gas with the product I have seen no difference in vehicle performance. I would not go out and buy this product.

[This review was collected as part of a promotion.] This seems like an effective gas additive. We put it in our 2015 f150 and we are getting better gas mileage and it runs a bit smoother. It's high mileage so we will probably start using this every time we do an oil change.