Volkswagen: volkswagen passat 2003, glx passat, volkswagen passat

Question
Hi my name is Tommie I'm currently looking into buying a passat it is in emaculant condition,and i plan on taking it to be looked at for a 112 pt check up. when i went to test drive the car the check engine lite was on. im not familular with the volkswagen make this would be my first buy. could you tell me from minor to serious what would make the lite be on in the car.im not familuar with german made vehicles. i just want an idea of as to what could make it be on. its a 2003 glx passat, and its got 70,085 miles. when i got carfax report it was clean. before,i buy it i will have it checked out, but from what you know is there anything you could tell me abnout this make and model of car as to the difference as when the check engine lite comes on in any vehicle, is there a difference with this being a foreign make? could it perhaps be something as small as the oil need changing as to why it would be on. i dont want to purchase a lemon if you know what i mean.  

Answer
Hi Tommie,

This usually denotes a minor emissions problem.  The most common cause of this is an oxygen sensor or a leaking full cap.

I would certainly have these replaced at the expense of the seller and the light turned off prior to buying it.

Sorry for the delay getting back to you.

Ron