HOW TO USE SEA FOAM MOTOR TREATMENT IN FUEL
BENEFITS
applicationS
treatment recommendations
SUMMARY
Pour Sea Foam in your fuel tank to clean and lubricate your entire fuel system. It works through fuel injectors and carburetors to remove harmful residues and deposits from fuel passageways, intake valves, pistons, and chamber areas.
For cleaning a gasoline or diesel fuel system, it’s safe to add more Sea Foam to fuel. In fact, the more Sea Foam you add to fuel, the better it cleans!
Made from petroleum ingredients, Sea Foam is safe and effective when used in all types of gasoline or diesel fuels and fuel blends. Sea Foam does NOT contain harsh detergent or abrasive chemicals that can harm your engine or fuel system components.

HOW TO USE a high concentration of SEA FOAM
mOTOR TREATMENT IN FUEL
RELATED QUESTIONS
Can I use Sea Foam for a 2014 Chevy Impala 6 cyl?
Thanks for the question!
Yes, you can absolutely use Sea Foam Motor Treatment in your 2014 Chevy Impala V6. You can use it in the fuel and engine oil.
For the best fuel-system cleaning, I’d recommend waiting until the tank is low (about 1/4 tank or less), adding a full 16 oz can, and then driving at least 10–20 miles before refueling. The higher concentration works much better and faster to clean fuel residues and deposits.
You can also add Sea Foam to the engine oil at 1 oz per quart of oil, about 100–300 miles before your next oil change. This helps reliquefy oil residues and deposits so they can drain away with the old oil.
I have a 2005 Toyota Sienna that has been sitting for about 3 months over the summer with a quarter tank of gas. I need to start driving it again, but will only be driving it intermittently. It may take me another 3 months to go through a tank. Should I put Sea Foam in my quarter tank and then completely fill the tank?
Great question, Neal. There’s two things I’d think about when considering fuel that sits for a while. First, you’ll want to think about cleaning up any fuel varnish that formed while the fuel sat. Second, you’ll want to think about preventing varnish from forming during future periods of inactivity, as well as preserving the fuel’s ignition vapors.
A tank of fuel that sat for three months will still be just fine to run.
I’d take two simple steps:
- First, especially if you’ve never done it before, run a strong cleaning concentration of Sea Foam High Mileage through your Sienna. That will clean up and fuel residues and deposits throughout the whole fuel system. It’s a great thing to do in any vehicle. A quarter tank is actually a perfect time to add Sea Foam. Here’s what I’d do: add an entire 16 oz can of Sea Foam High Mileage to your fuel tank, drive until almost empty (just don’t run out of gas), and then refill your tank. The high cleaning concentration will work much better and faster than adding Sea Foam to a full tank.
- Second, you can protect the fuel that sits in the tank by adding a can of Sea Foam High Mileage (or Motor Treatment) to every tank of fuel. Just add it before you fill up. That will help prevent gum and varnish from forming and prevent the fuel from degrading.
I have the Sea Foam High Mileage that I’ve had for a couple years for my 2006 Ford Taurus, which I don’t have anymore. My question is can I use this High Mileage Sea Foam for my 2024 Civic SI?
Hey Lonzo,
Thanks for the question. Yes, you can use High Mileage for your 2024 Civic. High Mileage is a great cleaner – it’s formulated to clean stubborn deposits and residues after years of buildup. But you can absolutely use it in a lower mileage vehicle too. It’ll do a good job cleaning up the fuel system.
Here’s what I’d do:
- Wait until the tank is low (about 1/4 tank or less)
- Add a full 16 oz can of High Mileage
- Drive at least 10–20 miles (or until nearly empty) before refueling
The high concentration works much better and faster to clean fuel residues and deposits than adding the same amount to a full tank.
I used a bottle of Sea Foam Motor Treatment and it has improved my rough idle and stalling but not completely. Can I use another bottle right away?
Thanks for the question!
Yes, you can use another treatment right away. I’d recommend High Mileage Sea Foam since it’s formulated to be a strong cleaner for stubborn fuel residues and deposits. Here’s what I’d do:
- Wait until the tank is low (about 1/4 tank or less)
- Add a full 16 oz can of High Mileage
- Drive at least 10–20 miles (or until nearly empty) before refueling
The high concentration works much better and faster to clean fuel residues and deposits than adding the same amount to a full tank.
If deposits are causing the remaining rough idle and stalling, another high-concentration cleaning treatment should help. If the problem continues after cleaning, there may be another mechanical or ignition issue that needs to be checked.
Steps to clean a 3 gallon plastic fuel tank with excessive sludge and varnish using Sea Foam?
Thanks for the question, Harold. Yes, you can use Sea Foam Motor Treatment to clean the excessive sludge, gum, and varnish from that 3-gallon plastic fuel tank. We received a very similar Q&A question a while ago. You can read that here:
I’d recommend a 50/50 mixture of Sea Foam and fresh gasoline for a heavily contaminated tank.
Here’s what I’d do:
- Drain and dispose of all the old fuel first.
- Mix Sea Foam Motor Treatment and fresh gasoline at a 50/50 ratio. You don’t necessarily need to fill the entire 3-gallon tank. You just need enough mixture to cover the contaminated areas.
- Make sure the mixture reaches above the highest varnish or contamination line inside the tank.
- Let it soak for 24–48 hours.
- Periodically move or slosh the tank around so the mixture contacts all of the contaminated surfaces.
- If possible, leave the tank outside in direct sunlight while it soaks. A little heat will help Sea Foam work faster.
- When you’re finished, drain and properly dispose of the Sea Foam/gasoline mixture.
Sea Foam will work to reliquefy the petroleum gum, varnish, and sludge so it can be drained out. If there’s actual dirt, rust, or other solid debris in the tank, that will need to be physically removed. Sea Foam won’t dissolve that type of contamination.
For really heavy buildup, don’t be afraid to repeat the process.

Jim D.TECH
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