fuel smell, losing fuel, car dies going down rd with no warning, will start back up then acts as if running out of fuel regardless of amount of fuel...

A bad O2 sensor would not cause the fuel smell. O2's are mounted in the exhaust system. I'm going to state the obvious and say you have major fuel issues. Have you checked for any fuel leaks under the car or hood? There could be a broken, rotted, or disconnected fuel line in the system causing a fuel pressure loss.