I am having the same problem with my 2000 A6 Quattro Wagon. I am not sure where/how to check the below stated:
P1423
17831
Bank 1, Secondary Air Injection (AIR) system Throughput too low 1)
- Check fuse for Secondary Air Injection (AIR) pump
- Check vacuum hose setup
- Check hose setup from pump to combination valve for Secondary Air Injection (AIR)

Can any one give me directions and possibly a pic or two on how to replace and check the hoses, valves and location ofthe fuse.

Greatly appreciated,
g_whitloc

 

This looks common. Has anyone with this issue actually had it fixed for a reasonable price. I've got the same code for about 6/7 months now. I think the book said it was secondary air injection system low flow.

- Has replacing the fuse actually helped on this one?

 

this thread is from '06....