I have 2003 A6 3.0 with 56,000 miles. My malfunction indicator light came on last night. After reading the some of the posts here I took my car to Autozone for a diagnostic check and it came back, Secondary Air Supply, Bank One. Can someone please explain if this is serious? Thank you for your help.

 

not until you have it inspected, or go to emissions.. whatever your state does.. basically the secondary air just injects air into the exaust durring the warm up period to light off the cat quicker. once the cat hits operating temp the secondary air is shut off. so if the fault is that the valve is not opening then youll be fine until emissions time.