One problem related to check engine light on has been reported for the 2001 Volkswagen GTI. The most recently reported issues are listed below.
My blinkers stopped working in August 2002. Dealer repaired under warranty. January 2003 check engine light came on. Car off warranty; turbo cut off valve replaced and coolant temp sensor. Check engine light came on a couple weeks later. Took Gti to dealer again. Dealer replaced the fuel pump relay. Now, 3 days later the check engine light came on again.