Got this error code P1626 Data-Bus Powertrain Missing Message from Transm.Contr.

is it fixable without being costly

 

It could be as simple as a wet/damaged ECU or TCU. Some people get really lucky and simply dry out a TCU and have it working again, others need to buy a new one for a few hundred dollars (?? i'm not sure how much it is). Sometimes the error will come up if your ECU is programed for an automatic transmission when you have a manual. The error essentially is saying that there isn't good/any communication with the TCU.

But seriously, http://www.lmgtfy.com/?q=audi+P1626

edit: and since i'm nice - http://forums.audiworld.com/showthread.php?t=2780480