On the floor, next to the driver's side door, there is a release latch, pull it toward you.
My base Vibe (1.8 L) is 12 gallons.
13.2 gallon
in the gas tank.
13.25 dry.
unlock all the doors and then push the right side of the flap.
You will find that info in the owner/driver's manual.
If it's like my 2006 Vibe, the fuel filter and pump are one unit and it's located inside the gas tank.
The 2005 Pontiac Vibe is comfortable to ride in and the back seat is roomy. There is a good storage area and the gas mileage is good. Also, there are power locks, OnStar, leather seats and side curtain airbags.
I get about 400-450 depending on amount of city/hwy driving
Fuel tank (gals / L) Base & GT13.2 / 50AWD11.9 / 45
Right next to the driver's seat on the floor, there is a small pull tab. This releases the cover of the gas tank.
80 miles on highway give it a try and let me know how it turns out