It should run from the intake manifold, to the front core support, over the top of the fresh air intake for the air box, along side the left front fender,and then through the firewall and into the passenger compartment. Right about where it goes over the air intake duct there is a short piece of rubber hose that butt connects the plastic pipe, see if you have not knocked it apart right there. Otherwise check it out where it connects to the manifold itself, I think it is right there at the vacuum tree by the throttle valve end of the intake manifold.

Mark