S4 singing the siren song

[Jester B]

So, when my '01.5 Tip S4 is driving along in traffic and I'm very gently on and off the throttle, I'm finding myself looking for the cops from the siren sound my car creates.

I've searched the other forums (Audiworld, etc.) and can't find anything conclusive on this. I "think" I'm hearing the turbos starting to spool up and then back down again, creating this sound, but have also had it suggested it could be the tranny. Doubt it's the tranny.

Any experience with this? Car's going into Glenmore next week for cam tensioner seals / timing belt / etc. and I'm going to get them to listen to it then, but want to go in "armed" with more info than just "it's making a noise".

Could it be a boost leak? Was just in for service and nothing came up on VAG that they told me about.

Thoughts? If they's gonna blow, I need them to go soon before my CPO warranty expires in the spring.

[stefan]

Re: S4 singing the siren song

fwiw, my good friend is a heavy duty mechanic that just finished school. in their unit on turbos, their instructor had said that if you are getting siren sounds, your turbo is on it's way out.

[The Brice]

Re: S4 singing the siren song

Jeff as long as they are not getting loud your okay, mines the same way, and with my boost guage I can see it's just around 0psi where this occurs, or right when the turbos would be starting to spool up. Mines fairly quiet on start-up and by time the motors nice and warm hardly noticable at all. I've heard it's time to start worrying when you get the infamous screaming babies sound or like a loud dentist drill, you can go on youtube and dig up a few S4's with the dying turbos for a comparison. Oh if you notice any smoke starting to pour out the exhaust can also be a good sign of dead/dying turbo(s).

[R_Ethug]

Re: S4 singing the siren song

is yours still under CPO for the timing belt??? if not how much is glenmore charging you then? i'd be curious

[Jester B]

Re: S4 singing the siren song

is yours still under CPO for the timing belt??? if not how much is glenmore charging you then? i'd be curious

Not for the belt. Doing the cam seals under warranty. Since they are "there", I'm getting the timing belt and all related done on my nickel. Will be about an extra $400 for me to do this, but at $1200 or so for a "normal" timing belt job it's a no-brainer.

Having them "listen" to the turbo sirening and going to get them to give an opinion on motor / tranny mounts. Getting a slight, ever so slight, vibration under moderate acceleration. Reminds me of when my rear mount was busted on my 1990 Corrado G60.

[R_Ethug]

Re: S4 singing the siren song

the vibration could be caused by a axle/cv issue.. when my cv tore when i accelerated and slowed down it would wobble wobble vibrate on me annoying as fark

[Jester B]

Re: S4 singing the siren song

the vibration could be caused by a axle/cv issue.. when my cv tore when i accelerated and slowed down it would wobble wobble vibrate on me annoying as fark

Interesting though. George did highlight on the pre-purchase inspection that the boots are starting to crack (on my list of things to fix pre-summer). Vibration is more of a 'buzzing', though. I'm kind of expecting the car to be quite smooth on acceleration. It's smooth, but not "silky smooth". Am I expecting too much?

[The_Jerbel]

Re: S4 singing the siren song

yes

[Smarty39]

Re: S4 singing the siren song

I'd say your turbos are still okay...until they sound like screaming babies! Mine are loud as hell, but still not unbearable...but they're still getting swapped out. My bet is the dealer will just say that it's normal, even if it isn't, because god knows they don't want to pay for the job under warranty.

[The_Jerbel]

Re: S4 singing the siren song

Just an idea, but if you want me to listen to your car for you we could meet up sometime. That way you could get a 3rd party opinion.

[Jester B]

Re: S4 singing the siren song

Just an idea, but if you want me to listen to your car for you we could meet up sometime. That way you could get a 3rd party opinion.

I may take you up on that (when it's warmer). Appreciate the offer.

[VWSM]

Re: S4 singing the siren song

I pulled out my crystal ball turbos it says.
anyhow if they say it's normal have them put it in writing.
if you ever spun a bearing without lubrication thats what it sounds like.