Can I add Sea Foam in my 1998 Honda civic DX hatchback motor oil? [SOLVED]

Thanks for the question!

Yes, you can add Sea Foam Motor Treatment to the oil in your 1998 Honda Civic DX. Add 1 ounce of Sea Foam per quart of oil in the crankcase. We recommend adding it 100–300 miles before your next oil change. That gives the Sea Foam enough time to circulate and clean, and it allows the reliquefied oil residues and deposits to be drained away with the old oil.

Sea Foam in the oil works to clean oil residues and deposits that can build up over time and restrict oil flow.

Just be sure not to exceed 1 ounce per quart of oil.

Hope that helps and let me know if you have any other questions!