I finally got down to taking care of the CEL P0401 ... took apart the EGR manifold ... couldn't believe how bad the carbon was.

Cleaned it all out, used a drill bit by hand on the manifold side (didn't take intake off) with a shopvac on at all times to suck it all up.

Replaced injector seals, gaskets, replaced a bunch of vacuum hoses and some return fuel lines ... WOW, what a difference in the way the car runs ... totally amazed at how much quiter and better idling ... should have done this 100k miles ago!!