OK first:
The fuel DOOR will NOT cause an engine light.
The fuel CAP WILL cause an engine light

second:
You probably need the whole housing part# 5099987AA
I would consult your local parts department though.

OK, Shawnkey,

Maybe I wrote it down wrong. Andrew had me check the gas cap, then drive the car a few times, and the engine light went off. Whew!

I will go out a try now what Aknester just mentioned.

And Shawnkey, thanks for your input, it really is appreciated...