I just finished the timing belt on my 1999 A4 Quattron 1.8T. I put everything together and found this sensor hanging below and behind my radiator/bumper. Does anyone know what it is and where it goes. Thanks, I've spent a lot of time on this and I'm stumped.

 

It bolts onto the bottom of your radiator. There should be something else that bolts on top of it but i don';t recall. But I'm possitive it bolts directly in the middle on the bottom of your radiator, you could probably get to it with just taking the front bumper off.

 

You may even be able to reattach it by pulling the bottom center grille off the car.

 

yeah, its your exterior temp sensor. The power steering cooler line - the long loop in front of the rad - bolts on top of it.

Look at picture in part #8 and # 9 HERE