I have a 2011 Mazda RX8 with heavy engine carbon buildup. What is the maximum I can put in the fuel to try and clean the carbon from the inside of the combustion areas? I cannot do the heat soak treatment because of the smoke it will produce so adding to the fuel tank is my only option.
Hi James. If you can’t use Sea Foam Spray through the intake to clean carbon form the combustion chambers, an alternative would be to add a few cans of Sea Foam High Mileage to fuel when the tank is very low. The higher the cleaning concentration, the better and faster it cleans. After you add the cans to a low amount of fuel, you can drive or run the engine for 5 minutes, then shut it off to let the chambers hot soak for 10 or so minutes… then repeat the sequence until you’re ready to add fuel. Hope this makes sense!