[alia176]

Back in the old days, we used to let the intake suck in water through the intake and flash steam clean the combustion chamber, and the valves. Obviously you have to be careful and don't hydro-lock the engine but this archaic method did wonders for some of those old V8s. I still do this to all of my vehicles from time to time, including the SVX along with seafoam and BG intake cleaner (using BG's spray wand).

Bottom line is that you're trying to clean up the intake air tract that gets coated with PCV and some EGR crud. Contrary to what some may say, cleaning up the combustion chamber using water or products like Seafoam is still very difficult to do. About the only way to clean up the combustion chamber is to open up the engine and physically scrape up the varnish until the shiny alum of the pistons peek through.

Perhaps a PCV catch can eliminate lot of the gunk from re-entering the engine. On my other two vehicles, I've installed a simple air/oil separator into the PCV lines and it's eye opening as to how much oil it captures. I may do something similar in the SVX once the upper intake is back on the engine with fresh new hoses and gaskets.