The Seafoam eats off the carbon buildup and any other oil based crud that might be in it's way. It's great stuff to keep overhead cam motors from throwing off cam followers. The smoke is that junk burning away.
Ive got a can of this stuff sitting in the garage and might have some time this afternoon to do it. Majority of reviews I have read are very good but every now and again youll see someone say DO NOT put into your crankcase, dispite the instructions telling you to add 1/3 of it to the oil. Fuel is fine, intake is fine oil NO. Anyone care to comment on that? I got a new PCV and EGR valve to replace this weekend along with an oil change im going to do, should I just stick with doing those things and seafoam in the intake and fuel and leave it out of oil? I wanted to do the seafoam before I put the new PCV and EGR valves on. I dont want to screw anything up and have it clean the crankcase soooo good it starts leaking somewhere. I have an 04 5.7 hemi with 105k miles on it. Thanks