Originally Posted by Padgett

P2017-1
MIL ON&Stored&Current
Self-adaptation of mixture formation for right bank of cylinders is at limit value (at idle speed). Enrichment over permissible limit (P0171)
P2086-1
MIL ON&Stored&Current
Self-adaptation of mixture formation for left bank of cylinders is at limit value (at idle speed).: Enrichment over permissible limit (P0174)

Been getting these about every 50 miles, mixture on both banks ramps way up at hot idle indicationg lean mixture on both banks.
Replaced MAF and O2 sensor, no change.

Anyone know what the idle manifold vaccuum should be ? Other suggestions ?