Hey guys I just recently bought a 1999 Audi A6 with 88k miles and the Check Engine Light came on.
Here are the codes


P017544 Bank 1 LongTerm Fuel Trim
16825 Evap Emission Control System
16839 Evap Emission Control System
17546 Bank 2 Long Term Fuel Trim
60326 Brake Light Switch

The car drives fine. I dont notice anything unusual. Any ideas on these codes?

 

Both of your EVAP codes need to be addressed for emmisions purposes, the first evap code is stating there is incorrect purge flow. Replace the N80 valve. Thats on top of your airbox, with a single connector and two hoses going into it.
The second EVAP code is saying there is a "gross" leak meaning there is either a huge freaking hole in a line somewhere or your gas cap is bad. Get under the car and look on the passenger's side from the back to the front to see if there is a hole in any of those black plastic evap lines. (NOTE: If you had a tire blow out in the right front it often damages the EVAP lines there)

For the fuel trims, change your air filter and clean your MAF sensor with some electrical contact cleaner then clear the codes and see if it comes back.

The last of course, replace your brake light switch.

 

I cleared the codes and a day later I get P0455 and P0441.

From what I read its a bad gas cap. But my gas cap seems fine. Any other ideas?

 

i have a very good idea of what it is! you are going to have to buy a part. It is called Evap control module i think but it is under the cover on the passengers side under the hood.! if you have any more quetions let me know

 

I tried a gas cap and that didnt fix it. How can I be sure Its the Evap contrule module?

 

im still stuck with p0441 and p0455.... I checked the things you mentioned and they seem fine....Any other ideas? I have access to a VAG-COM. Can i do anything with that?