As for the wierd smell from your vents, I doubt that has anything to do with your gas mileage. You may want to address that in another thread. But be a bit more specific about when it happens and whether the occurances are random or happen when you have the heat or A/C on, etc.

O2 sensor... Like Vital says, it would help us to help you if you would go to the top of the page, click on "Profile" and put your car'* year and trim level in a signature line. That having been said, and since I haven't read all your other posts:
What is your mileage?
How long have you personally had this car?
And what mechanically have you done to the car, if anything?

He'* a 95 SE in the meantime of adding it.

Recent items done were cleaning of MAF and IAC. This helped idle and caused a heavy foot problem IIRC.

Nope. No one around with one. You coming up early?

i just filled up again today with 16.5 gallons
gonna see how this tank holds up? and if it sucks again i guess ill replace the o2 sensor ...wish me luck haha

Luck on the tank or sensor? Sensor is cake..I've got the tool for that. (If you didn't already guess that one..lol)

the tank haha. i figured you had the tool haha