[brucepick]

I've seen loads of good writeups from guys who have used Seafoam.

I've used it several times but it did not fix the problems my engine had at the time. On the other hand, it caused no damage either.

My Civic engine turned out to need a proper head rebuild. One valve was badly burned, it needed four (or eight??) valves replaced, and piston tops were hard-coated with carbon buildup - I removed that with a brush head on a Dremel type tool.

Anyway, I've seen loads of guys who love Seafoam and I wouldn't hesitate to use it. I use Marvel Mystery Oil in my fuel, at half the concentration the bottle recommends. But that's another story. You can read about MMO on bobistheoilguy.com if you care to.