P0411 CEL and weird noise when cold
 

ok so lately there has been a shearing noise coming from the right front side of the engine bay upon startup. it lasts about two to three minutes and then goes away. the best way to describe the noise is "sssssssshhhhhhhiiiiiiinnnnnnnnnggg" its ongoing for a few minutes but if I accelerate it goes away and doesnt come back.

I was thinking secondary air pump thingy. the other day i get a cel P0411 so i figured my gas cap was loose I tightened it, cleared the code and was good for a couple days. then it came back. i cleared it again and another few days went by and it came back. no big deal its not blinking so i dont care about clearing it now and then.

would that airpump be causing this code and/or noise? anyway I can get to the pump to check and see if its operating. anyoneelse hear of this problem or have a quick fix? how much are those pumps andcan it be a DIY? i've heard $400 + for the pump but i'm not sure. audi will tear me a new one if i bring it in thereand i know that pump isnt going to cause any major problems (i dont think) how major is it?

until I hear back from someone who knows what this could be i will be searching i appreciate any responses thanks....

RE: P0411 CEL and weird noise when cold
 

Yup I have that noise too. Its the bearing(s) in thesecondary air pump. I dont have any fault codes to go with my noise, but I know exactly what youre talking about. Happens to me for about 1-2 mins only on a cold start. Its been that way for over a year... Eventually Ill take it appart and replace the bearing, but until it gets too unbearably loud I can live with it... In fact I forgot all about it until you brought it up.

RE: P0411 CEL and weird noise when cold
 

I just searched and found that odds are its the pump itself (under passenger headlight?) the solenoid (near exhaust mani?)or the silver cylinder valve (near the firewall?) or possible any of the lines going to and from these things. I guess my question is: does it need to be fixed? does anyone have an extra laying around? btw: i'm at 160K miles.

tee: does it only happen to you when its cold out? its been in the 80's here and i still get it but only when the engine is cool. I guess thats what you mean. with the windows up i cant hear a thing but with them down (summer) i hear it as I accelerate and then it changes pitch and fades away. probly same exact thing. theres numerous threads relating to this. I guess its not worth fixing since it isnt damaging anything really.

also, my car idles high for a minute or two upon starting are you getting that as well? once I let it idle it goes down to about 800-900 rpms. but at first its like 1100-1200 rpms. what is the cause of this or are our cars justmade to do that normally. Germans...

RE: P0411 CEL and weird noise when cold
 

Doesnt need to be fixed. Its only to aid in cleaner emissions on a cold start before the 02 sensors get heated up, etc. Ive never read anything about the solenoid/silver cylinder valve... Got a link for that?
There is a writeup somewhere that tells how to take the airpump out, crack it open and service it. I thought I had it on my computer but I dont... If you find it let me know. I would only attempt to fix/replace if I had a constant CEL from it, which will happen eventually... So go search for that writeup :D

RE: P0411 CEL and weird noise when cold
 

https://www.audiforums.com/m_242422/tm.htm

looking for the DIY writeup. probly pretty simple if it is where i think it is (under the headlight). couple of bolts, a couple of hoses, bada bing, bada boom, new useless air pump, no noise and $$$ in the hole... Germans...

RE: P0411 CEL and weird noise when cold
 

Thanks

RE: P0411 CEL and weird noise when cold
 

According to Bentley, it could be the secondary air injection solenoid valve (N-112).

RE: P0411 CEL and weird noise when cold
 

OK I fixed this problem. I was putzing around the engine bay when I see a crack in the hose coming up from the secondary air pump. I wiggled this L shaped hose connecting two hard lines and it completely broke off. I got the part number replaced the hose (then ends were melted to the hardlines right above the turbo) and now I have not heard the noise since. If anyone is experiencing this check the l-bend hose and see if it is still in tact.

RE: P0411 CEL and weird noise when cold
 

well done:) exactly what the book says;)

[IMG]local://upfiles/12092/82F2E83DD709433E8BB474FAC7810C6D.jpg[/IMG]

RE: P0411 CEL and weird noise when cold
 

I sometimes wish I had one of those "books"