Part Identification

Pontiac Grand Prix auto 38k miles.
On the driver side. on the rear of the manifold just under the EGR valve is a small black part with a couple wires connected to the top and small hose running back to the firewall and down towards floor. the hose is wrapped in black flex cover.
What is the name of this part, and how do I replace? the tube leading out of it is broken and it is giving check engine light and check gas cap.

Thanks
I can upload a picture later if requested.

thanks in advance

Dan