Engine flush??? I know PB Blaster makes a chemical for flushing and revitalizing transmissions that are dirty and slipping. I was woundering if the liquid form of it inthe gallon container would clean deposits out of an engine with out harming anything else? Seems like it would get under deposits and get directly into the pores of the metal and force junk out? The question then would be how long could you leave it in and would it hurt seals? I am guessing here but since it is much more mild then B12 I can not imagine it not being able to be left in for the duration of an oil change? Any idea's????

I would say don't do it.

Not because PB Blaster won't clean - it probably will help the cleaning process a lot, but some of the ingredients in PB Blaster are not combustible and will do very strange things in the combustion chamber.

I dripped some PB Blaster on some linoleum and it softened and raised it. No way I'd put it in an engine or transmission..

Marvel Mystery Oil mixed as 20 percent of crankcase capacity and engine run gently gave me some really good results. Not as fast as some motor flush chemicals, which I think is probably a good thing.