i keep hearing of people using seafoam. what is it, how does it work. is it a gimmick like some of that fuel injection cleaner, octane booster, millage booster, and other "magic chemicals" that really do nothing. does this stuff actually work? can a seafoam treatment screw up an otherwise good running but high millage engine? how much should i expect to pay for a bottle? how is it properly done? my car runs really well but it has well over 100K on it. i have changed the oil regularly, but dont know the past history. does not burn oil, gets good pressure. i feel that a treatment might clean up 100K of carbon and crap. advice on this product?

 

http://www.seafoamsales.com/products.htm

I've never used it personally, some people swear by it, I've never heard of it causing damage (but I haven't necessarily heard everything).

 

Yea, it's kinda a magic mystery cleaner.
You can use it 3 ways, each way requires about 1/3 of a can. Coincidence?

Anyway:
1) through the intake manifold vacuum (tried it, works great at cleaning out your combustion chambers.
2)in the fuel tank. I don't think this is nearly as effective.
3)in your crankcase. Apparently this cleans it up. I'd be wary of this, or only do it, then run the car 50 miles and change the oil. I personally wouldn't do it long term.

You should be able to get a can for under $10. Maybe $14 tops. Look at the website for pictures. It's not in every store, but the good places should at least know what it is and where you can find it.

 

You can get it at stores like O'Reilly auto parts, Advance, Auto Zone, etc. for about $5-$7. I've used it twice. Didn't really do much for me, but have heard some people have a difference. It's supposed to clean carbon build up, free sticky lifters and rings, clean fuel system...

You let your brake booster line suck up like 1/3 tp 1/2 can, and pour 1/3-1/2 into the crankcase and then put the rest in your gas tank. After your car dies from putting it in the brake booster line, let it sit for like 30 mins. Then start the car and rev it and take it for a "spirited" drive. A bunch of white smoke will come out the exhaust. This is all the carbon it broke up. Mine didn't have that much smoke. Shortly after you'll wanna change your oil, and prolly the plugs and o2 sensor.