i've seen ambsoil(sp?) engine cleaner, in order to run it properly, you have to take out approximately 1quart of old engine oil off from your ride and then pour that cleaning solution into the engine and run your car at high idle about 20mins, but you aren't actually driving your ride, just idle at high rpm for 20mins and just drain out the engine oil.

i don't know how they work out good, but i would like to do some sort of engine clean sometime this summer time if possible, my engine has been running for last 10yrs!

$.02