I have been using it for a few years now. seems to help. I read a claim that it also helps stabilize ethanol fuel. I put it in all my small engines now just for that reason. So far, I have not seen any negative effects, and the fuel does seem to last longer.
Here is my two cents. If you have a GM vechical with the 3.6 V six and you pop a check engine light PO24 code. Variable cam sensor not responding. It is caused by dirty oil and scum build up in the cam chain area. The fix for me was a half can of sea foam in the oil. Run the car 4-500 miles and change oil. Light went out and has not come back on. Now I am changing oil more often and have not had any check engine lights. I think seafoam will help clean an engine internally! JMHO!
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