Volkswagen Repair: malfunction indicator lamp, obd ii, literary hundreds

Question
passat 2004 1.8t
that light came on tow weeks a go and went off.
to day came on again, what is the problem.

Answer

Actron_CP9125 Zoran,
I am assuming you mean the "Check Engine" light.  This is a non-specific indication telling you the computer has detected a malfunction.  There are literary hundreds of reasons for this.  You need to have an OBD-II scan to pull the error code from the computer.  You can get one for less than $70 US:

http://www.amazon.com/gp/product/B0007LEG2K

Then go here to look it up yourself if you wish.

www.obd-codes.com

- Rick