RepairPal Certified shops can diagnose and repair your 2004 Volkswagen Passat. They provide transparent pricing with a minimum 12-month or 12,000-mile warranty on repairs and services.
Good grief, don't replace it with plastic crap!
Read this: http://www.dieselgeek.com/servlet/Detail?no=374
Mine was $280 SHIPPED, it took less than 20 minutes to install this peace of mind.
Yes, it is on the bottom side of the engine but not part of the bumper.
I think its called an Undercar Shield $283 available at : http://www.pelicanparts.com/euro/catalog/shopcart/W088/POR_W088_BDYchs_pg1.htm#item5