What's problem with Volkswagen and Audi diesel engine?

I'm interested in Volkswagen and Audi TDI engine.


But I don't know that TDI engine's serious problem


What's problem with Volkswagen and Audi diesel engine?


Please help me increase of my diesel knowledge.|||The engines will self destruct if they have a timing belt rather than a timing chain and the belt breaks, so make sure to have the timing belt (and maybe water pump and belt tensioner pulley) changed at no more than 100,000 miles or 7 years, or whatever the manufacturer specifies in your manual.








http://www-odi.nhtsa.dot.gov/cars/proble鈥?/a>





http://www.mycarstats.com/





http://www.edmunds.com/maintenance/Maint鈥?/a>





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