yes, they can fail pretty quickly and the reason is plain and simple: they are ****. So again, as for post #2, go for the pierburg one, did it on my 110 and never had a
problem. the pierburg maf costs less than a half than the bosch one, doesn't break, doesn't get dirty and my car felt a lil more responsive at low revs after putting one in. do a search here in the tdi section or take a look in the tdi faq's, there are some posts/thread of mine that contain all the part #s and info about the matter.