Had my first audi for 3 weeks now and noticed it runs and idles terribly with the air con economy button on. Almost like a random misfire. As soon as i switch it off the blowers get much colder as it should plus the engine runs and idles great.

Its a 2007 A6 Avant 2.0 SE TFSI

Any help much appreciated.

Did you buy the car from a private individual or a dealership? 

If it were a dealership then I'd be taking it back for them to access it. 

Ive found this thread which might offer some help: 

https://www.audizine.com/forum/showthread.php/779675-Engine-shake-at-idle-worse-with-ac-on

Cheers

Steve

Steve

Thanks for your reply.

It was a private sale and didnt notice the issue on the test drive.

Checked the link out but my problem goes away when the a/c is on. Theres no codes showing. I guess i will have to live with it until i can get it to an audi specialist.

Yea I'd get it to a garage to get a diagnostic check carried out. 

Just to follow up on this, it turned out to be faulty #1 injector.