Speedy4x4 -

Pulled vacuum - no .. would need to find out how
OBD w bluetooth adaptor - no- I simply go to an auto store for a read
... since I have 3 cars and kids that stop by with theirs, gettign an OBD reader might be a good idea. Any suggestions on what is good for the shade-tree mechanic?
Car runs well ... almost dies when the oil cap is removed
Replaced all 4 O2 sensors ... not sure what you mean, but we unplugged & unscrewed what was there and replaced with new ones

Graphite Ghost - I typically give it a few days to see how it is running, and then take it to the auto store for another code read to see if anything was resolved...