Glad to hear you got some progress. I'm a big believer in Seafoam, and they make a spray that might help with the EGR passages. I'm prone to tell you to take the shop vac and roto-rooter the passages out with some 14-guage electrical wire while sucking up the gunk-ola. Please note that the "-ola" designation indicates a combination of funk and liquidity, so as not to be confused with "funk-inski", which solely designates funk particulate of a dry manner. "Funk-inski-ola" is really not something you want to talk to the wife about, and even some guys are squeemish about it. "Funkus Gunkus" is the very worst, because it indicates a semi-organic matter that has indiscriminate breeding habits, much like the men around East Virginia (West Virginians are another story, altogether).