Lets play: Name that noise

B6/7 S4/RS4
#1

Figured I’d get you guys’ thoughts before I take her in.

The noise is coming from the front belt area.
Only happens on cold starts when its somewhat cold (< -10C/14F).
Goes away after 2 or 3 minutes.
Pitch changes with rpm.
Belt looks pretty good. Had it out for installing lwcp and it was fine. (Noise was there before too so no way at all related to lwcp)
Pitch doesn’t change with steering movement (unless the rpms fluctuate as a result)
I flushed the power steering fluid just last week and the reservoir is appropriately filled. Made no difference.

Here’s a video with the phone placed near the front.

https://www.youtube.com/watch?v=RN2G1LFCgb4

Any ideas?

#2

Something is not flowing good…aortic stenosis would by my diagnosis ;D

pump or hose

No idea just a guess

#3

Sounds like the SAI pump is on the fritz

#4

Yep.

It sounds like an electric motor or fan that is making noise. Try hearing if it is louder on the passenger’s side than compared to the driver’s side. The secondary air pump is under the passenger headlight so if it is that then the noise should be louder on the passenger’s side.

#5

what’s the prognosis on fixing that?

estimated cost overall?

#6

Remove it, get block off plates…get it tuned out.

#7

Thanks guys. The SAI is just required to heat up the cats faster on a cold start right?

If it does end up being this, it might just be easier to block it off and tune it out since our emissions testing is pretty lax now (Just check for CELs and readyness).

I’ll go take a listen when I get home and maybe see if there’s an SAI pump test via vagcom I could try.

#8

Yes.

That is what I would do.

The SAI test is in 01-engine electronics, basic settings, channel 77. The engine has to be running at idle and warmed up to operating temperature. I think you can also run an output test to see if the noise sounds like the pump running.

#9

Getting it tuned out…is that really as easy as saying ‘I’ll just get it tuned out’? I think you’d need some co-operation from a tuner to do that, wouldn’t you?

#10

Didn’t mickf bitch endlessly about his SAI delete kit but jhm’s inability to get him a tune as the flash server wasn’t up yet? Or did I just make that up?

As for our etests in Ontario, read up on how to get the car ready for an etest. They’re supposed to look for evidence of tuning shenanigans. I’ll just find the reference.

#11

The tuning portion of it is by no means “easy” (I would imagine) but I thought about removing my SAI just to have less crap behind the motor and in the engine bay. The JHM supercharger kit deletes the SAI and I spoke with JHM about getting the system readiness and all the BS tuned out and they said it would be no problem.

I assume it can also be done on the RS4, and I know we are not found of EBwerks, but they sell the RS4 block off plates. This is all I’m going off of so don’t take anything I say as 100% possible or true.