Vehicle: 2001 Mirage ES 1.8L

Whenever I get a car wash that includes a under carrige wash or if I drive through a deep puddle my check engine light will come on. My car will idol roughly until it dries out again. A mechanic friend of mine says that the underside engine splash shield is missing. Neither of us can find one these parts anywhere. I have found the side and front shields but nothing for the bottom or underside. First, can anyone cofirm that the mirage does in fact come with a shield for the bottom of the engine? Second, does anyone know where I can find one?

On my daughter's '00 DE 1.8 there is no front shield. I bought it for her new in '00 so I know that nothing has been removed.
FWIW
YMMV