Seems as though I have had this problem since I bought the car in 2005. Had the throttle body cleaned almost annually whic allows the check engine light to go out for maybe a month or so if I'm lucky. Its been on more than it hasn't accept for when it finally burned out but only until it was replaced. causes all kinds of error codes. Short to grounds mostly, & prompted replacement of the catalytic converter & engine sensors.
Bought the car Nov. 2000; light first came on the following year and just about every year thereafter. VW needs to do something for the consumer on this one. They must know this problem exist. In NYC it cost approx. $440. to fix this problem.