I was looking to put something into my A6 to improve fuel economy, any suggestions???????

 

That is a wide open question bro, you need to be more specific!!!!

OOOO

 

drive slower, no sudden acceleration and braking, leave room b/w you and the car ahead of you in traffic condition, follow the maintenance schedule. take care of your car... Keep stock size tires, check tire air pressure weekly,

You could also ride the bus/train to decrease fuel expense (not economy per se)

 

Beside chaning your driving style, you're going to have a hard time making the A6 a fuel efficient car. Even if you can do something that makes a 10% difference which would be a heck of a lot, that's only 1.8MPG or so which would save $6 at the pump (woohoo). Chaning your driving style can easily give you 20-30% savings though - for free. I would add that there are a ton of gimic items that you should not fall for, the tornado is a good example.

That said, what kind of milage are you getting, it should be right around 18 MPG city and 24 MPG highway (2.7T and 4.2), if it is quite a bit lower then there is probably something wrong with your car, in that case fixing the issue will save you $$ in the long run.