Why not add LTFT in while checking O2 data. Might be a clue to the vacuum leak. Upon seeing a very positive trim, you would have reminded yourself to check for intake leaks.

Im also really surprised you didnt have a P0174/P0171, for lean exhaust.

Good tip though.

Kevin Mowdy
Technician
USMC-Exercise Support Division
Yucca Valley, California, USA