Before servicing the rollover valve, make sure to release the fuel system pressure, because it will be under constant pressure all the time. Vehicles with a 26 or 34 gallon
Fuel Tank have two rollover valves-the higher one is unremovable because it's connected to the tank, while the second low rollover valve is placed on top of the
Fuel Pump module and can be changed or serviced alone. Because the rollover valves are built into the top of the 35 gallon fuel tank, any repair or replacement requires changing the entire fuel tank. First, unhook the negative cable from the battery, take off the fuel cap and empty the fuel tank. After that, take out the fuel tank and remove the tube connection at the valve. The rollover valve sits inside a rubber grommet; raise one edge and roll the valve away to release it. Take out the worn grommet. The grommet is installed first inside the fuel pump or tank module, followed by setting the valve in place with your fingers, closing the tank, filling it up and installing the fuel tank cap. Hook the negative battery wire back up and start the automobile for some final leak testing.