SeaFoam makes many products to clean and treat your engine. This one can be added to the gas, oil and even into the top of the cylindars to help clean out the valves, etc. About 1/3 of the can is all you need.
Comments: I did the Seafoam treatment before a plug/oil change. I tried to do 1/3 can; intake sucked the whole thing up quick, fast, and in a hurry. Anyway, let it sit for 30 minutes.....after starting, looked like someone had thrown a smoke grenade in driveway.
Price: $6.99 Pros: It works! Cheap too. Cons: You need a container that will not be effected by it or they should change the can to leave a viewing port Recommended? Yes
Comments: The day before I an going to change the oil I dump about 2/3 of the can in the block with the oil and the last 1/3 I suck into the engine via any vaccuum line I can find, pulling until the engine starts to stall. Turn the engine off and leave it anywhere from about 20 minutes as the instructions say to overnight, which I did this time.
Turn the engine on and enjoy the show. Smoke and crud will fly with abandon from the tail pipe, leaving a nice black mark on the ground. About 10 minutes later it settles down and I change the oil. I have noticed that my truck runs a lot better after my semi-anual treatments, one time before the winter, and one time before the summer.