Draining the fuel tank

If it is nothing more than old gas, just go and drive it. I have two cars that regularly sit for more than a year. The gas in both of them is over five years old, but the engines start and run fine.

The easiest way to drain a gas tank is to disconnect the rubber fuel hose where it attaches between the body and engine, then bypass the fuel pump relay to make the pump run. Let the fuel pump into a can, then add fresh gas to the tank.