How to Use Seafoam in a Gas Tank
- 1). Locate the fuel filler port on your vehicle behind the rear driver's side or passenger's side door. Older vehicles may have the fuel filler port located near the rear bumper behind the license plate. Fill the tank to capacity with 91 or higher octane gasoline prior to adding the Seafoam.
- 2). Remove the cap on the fuel filler port. Insert a funnel through the port. Shake the can of Seafoam well and pour the entire can into the gas tank.
- 3). Start and drive the vehicle for a short distance. The Seafoam will mix with the gasoline, cleaning both the gas tank and the vehicle's fuel system. A large amount of smoke may come out of the tailpipe, but this is normal. Use the entire tank before adding more gasoline in order to avoid diluting the Seafoam cleaning solution.
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