So I went to the stealership, told them I was willing to chip in for 1 hour of Diagnostic time... No reprogramming necessary (so they say). I was told to replace the MAF (even though it was not reading out of spec) and that they really couldn't diagnose any further until the MAF replacement was done.
They told me that it is reading both Additive and Multiplicative faults on both banks.
Instead of the $429 they wanted (part with CCA discount plus installation), I have ordered one through getcoolparts.com for just over $200 shipped. It should arrive tomorrow, and we shall see.
The last 7 of my VIN are GM62871.
So how tough is the intake manifold gasket replacement? It doesn't look like it would be that difficult - thoughts, comments? Could I test for leaks by spraying air intake cleaner around the edges of the manifold?
What are the tell tale signs of the rear PCV Plate issues that you mentioned, above? How involved is addressing this kind of issue?