Thanks for the question! The 5.25 oz is IC5 Concentrated Fuel Injector Cleaner. It works to help recover lost power and restore lost fuel economy caused by dirty injector fouling.

Yes, you can just pour the whole bottle in your gas tank. One bottle treats up to 25 gallons.
For best results, add when the tank is low (1/4 tank or so) to maximize cleaning concentration.

Note: IC5 is a specialist, designed to clean fuel injectors. Our flagship product, Sea Foam Motor Treatment, covers broader applications. Motor Treatment will clean and lubricate the entire fuel system and anywhere fuel goes (including injectors). Both are good options. They just do different things.

Thanks for the question, Joe. Yes, you can still add the entire bottle to a 15 gallon tank. The higher concentration will work well to clean and it’s safe to add that amount.

Thanks for the question! Yes, you can add IC5 Fuel Injector Cleaner (or Sea Foam Motor Treatment, which cleans the entire fuel system in addition to fuel injectors) to your Nissan.

Thanks for the question, John! No, unfortunately the 5 oz bottle is the only size we sell.

If you want to treat larger volumes of fuel to clean fuel injectors, we have a 20 oz Truck & SUV size can of Sea Foam Motor Treatment, as well as a 1 gallon jug. You can find both of those at an auto parts store.

If you’re trying to treat large fuel tanks, you could also use a high concentration of Sea Foam Motor Treatment in fuel. Sea Foam Motor Treatment works well to clean fuel injectors. The idea is to add a small amount of fuel (2-4 gallons) and a whole 16 oz can of Sea Foam Motor Treatment. Then, drive until it’s almost empty to give the Sea Foam a chance to clean. The high concentration will do a great job cleaning, and you don’t need to fill the entire tank and treat all the fuel in the tank.

Thanks for the question. Yes, you can safely mix Sea Foam IC5 Fuel Injector Cleaner with other additives.