Hey guys I own a 99 A6 2.8 and my sec. Air pump has been no good for awhile now. At first it use to sound like a jet on start up but now it does the same but idles so low it almost stalls out. I bought a air pump and about to do the job and I was wondering if it ruined my cats. I get a sulfur smell and smoke on start up and than a gas odor coming out the mufflers after driving for quiet awhile. Will a new air pump work or do I need to replace Cats too.

 

If you are smelling something similar to rotten eggs, then it COULD be an indication that you're cats are gone. I'm assuming your are getting a CEL from the insufficient flow from bank one and bank two, no? Are you aware of any other codes?

I believe your o2 sensors (Providing they're healthy) will tell you whether or not the cats are working. If they both parity each other, then chances are your cats are no longer functioning correctly.

VAG-COM will be your best friend when it comes to diagnosing this problem... And most, for that matter.

 

The temp sensor some how wasn't plugged in. Why I don't in. I noticed it and its running fine. I do have another question if your good with these cars.

 

I'm fairly familiar with some of the systems on the C5 A6. There's no harm in asking, I'm sure someone here maybe able to answer it if I can't.

 

[QUOTE=Nebuchadnezzar;1436963]I'm fairly familiar with some of the systems on the C5 A6. There's no harm in asking, I'm sure someone here maybe able to answer it if I can't.[/QUOT
my car is throwing a code for the sais and the relay, as well as the evap purge control valve, but other than idling a little rough j don't see any other symptoms, is the problem more likely to be only one of the components? Help.this is my first audi, and while I love it, I have no idea what I'm doing.