Hello M.B.DOC,

Yes, the codes I showed were before replacing both O2 sensors and removing the MAF to clean its thin hot-film element with non-chlorinated brake cleaner. After the replacing them and clearing the codes, the check engine light stays OFF, so it seems that the replacements may be good at least for now. I think it may take more driving around in order for the trouble codes to show up again.

When I monitor the real-time air flow data using the OBD II scanner (autoxray), the number does keep increasing or dropping accordingly based on the engine RPMs (the minimum is 3.33 gm/s at idle), so the MAF seems to work even though it's probably still out of specs after the cleaning.

Since the vacuum pump was dead several weeks before the stalling problem started happening, so I was wondering whether its vacuum system plays a role in this stalling problem. A new MAF is not cheap (about $330).
Thanks.

Best regards,

Eric