Belt Tensioner???

Hi all. I have a few questions that I’m hoping someone out there can help me with. I have a 2001 VW GTI VR6, about 48K miles, and I’ve been his only owner. I recently replaced the starter; it was making horrid noises when starting. When he was at the mechanic he pointed out that the belt tensioner was cracked and needs to be replaced ASAP, which I have an appointment for. What would cause the belt tensioner to crack? I’ve put more money into him than I would like, replaced the engine ignition coil packs when the car was just over 2 yrs old (of course VW told me that my car doesn’t have the brand that are bad and are replacing for free) at the same time I had to replace the ignition wiring and spark plugs. Then there were the problems that VW fixed for free: window dropping into the door and the mass air flow sensor. And like I said above I just replaced the starter and soon the belt tensioner. I take very good care of my car (he’s my baby) and do more then the regular service maintenance. Anyone know of any more known problems I should be expecting? Oh, by the way I have an excellent mechanic, I don’t go to the dealerships b/c they are so untrustworthy.

Thanks for your help.

Oh, by the way I have an excellent mechanic, I don’t go to the dealerships b/c they are so untrustworthy.

Thanks for your help.

sorry to hear that, your starter and coil and belt tensioner would all be covered under warranty for free..

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