The only Sea Foam product that needs a hot engine when you apply it is Sea Foam Spray (intake cleaner).
For the rest of the products (Sea Foam Motor Treatment, High Mileage, Trans Tune, any others) it does not matter if the engine is hot or cold when you add it.
The only Sea Foam product that needs a hot engine when you apply it is Sea Foam Spray (intake cleaner).
For the rest of the products (Sea Foam Motor Treatment, High Mileage, Trans Tune, any others) it does not matter if the engine is hot or cold when you add it.