Derek, that is the inertia switch and it is unrelated to the problem.
There is a vaccum hose that goes all the way back to the spare tire area. It connects to the Evap Cannister, which is a fuel fume eradicator. Make sure that line isn't bent, buckled, spindled, folded, or mutilated. You get the idea.
Could also be the hosing from the filler to the tank, the tank itself, or the evap valve, which I believe is up in the engine compartment, near the brake MC.