Dentist Sound only on cold start???

[patman]

I just picked up my 1st Audi a Stg2 B5S4 @ 60Kmi now 1.5 months ago. It drives Awesome, but Ko3 makes the dentist sound for the first 30 sec or less every morning on cold start & goes away right afterwards. No dentist sounds at WOT or high rpm. Is the turbolady trying to visit me or this is normal?? I ask cuz i want to know before i should bring it in to shop for inspection or just shop for bigger turbos soon.

[mholme]

You get a dentist drill sound just at idle when cold, or do you here the turbos spooling more when driving?

[patman]

You get a dentist drill sound just at idle when cold, or do you here the turbos spooling more when driving?

just at idle for 1st 30 sec or less, not when driving or turbos spooling

[Cactus00S4]

is ur car a tip or 6spd? my tip does it somtimes at idle right after start up, somone told me its the secondary air pump or somthing like that, is it faint or kinda loud??

[patman]

is ur car a tip or 6spd? my tip does it somtimes at idle right after start up, somone told me its the secondary air pump or somthing like that, is it faint or kinda loud??

it's tip too. then that's what it is then? it's faint. it drives perfect though. So do i need to replace the 2nd pump asap or what till i'll do my TB, WP, overhaul soon next 5k mi? I'll like to wait cuz still deciding to go w/ K04 or Rs6?

[S4shpion]

secondary air pump is for emissions only. My pump made that noise on its way out and then died. Replaced it with used pump and worked for a week then did that noise and died again.

[samtimtom]

I have the same sound after a cold start. Also a TIP. It seems to be getting louder and more noticeable. I can hear it faintly inside the car and it is pretty loud outside the car. Is this normal or does it mean the pump is going out?

[OldYella]

I get the same sound and im a 6 speed. I think maybe it has more to do with cold oil in the turbos?

[alias747]

I get the same sound and im a 6 speed. I think maybe it has more to do with cold oil in the turbos?

If the noise is only at idle and goes away after 30 seconds I don't see in any way how it would/could be the turbos. When your car is idling your turbos are not spooling. They are spinning a little from the exhaust coming out, but not enough to make any noise. The air pump sounds more like the culprit.

[bayareaa6]

my 2.7T A6 also had secondary air pump issues when i first purchased the car. Usually in more damp conditions the secondary air pump collects water and will at times make the noise that is described in your post. Being that the secondary air pump is an emissions tool to warm up your cats i would not worry so much as to it doing any major types of damage to your engine or turbo.

[patman]

my 2.7T A6 also had secondary air pump issues when i first purchased the car. Usually in more damp conditions the secondary air pump collects water and will at times make the noise that is described in your post. Being that the secondary air pump is an emissions tool to warm up your cats i would not worry so much as to it doing any major types of damage to your engine or turbo.

Thanks bayareaa6!!! I think that's it cuz i live 50 yards from the pacific ocean & this morning it didn't make the dentist drill sound after 1.5 months of ownership. How weird & coincident. U guys are awesome here!

BTW I like this car so much that my other cars are not being touched as of late. Audi are awesome cars, i didn't know what i was missing out all this time.

[alias747]

BTW I like this car so much that my other cars are not being touched as of late. Audi are awesome cars, i didn't know what i was missing out all this time.

Welcome to the family man and I hope you are ready for the long haul ahead! Once you get in, you ain't ever gonna leave! :D

[patman]

Welcome to the family man and I hope you are ready for the long haul ahead! Once you get in, you ain't ever gonna leave! :D

Thanks bro! IMO The Audi is the perfect ride cuz it handles like a M but not as raw & at same time luxurious/comfortable like an AMG ride feel.

[obijohn22]

It is definately not the turbos, I have a tip and have the secondary airbox noise at cold start up also. If your turbos are going, you will not have to ask. You will definately know. Plus some "whine" at idle is common, not normal but common. very very faint. The problems come when you have strange noises under boost. at idle these cars make all kinds of rattles and noises that are out of the ordinary. Anything that is repeatable like that and just goes away after a fixed amount of time is something being turned on and off. freaked me out when i first got my car too lol....

[patman]

It is definately not the turbos, I have a tip and have the secondary airbox noise at cold start up also. If your turbos are going, you will not have to ask. You will definately know. Plus some "whine" at idle is common, not normal but common. very very faint. The problems come when you have strange noises under boost. at idle these cars make all kinds of rattles and noises that are out of the ordinary. Anything that is repeatable like that and just goes away after a fixed amount of time is something being turned on and off. freaked me out when i first got my car too lol....

Hey thanks for clarifications & reassurance there. I knew heading in that these FI machine aren't simple, but i can handle it. I did my research on this forum before i bought my ride too. My other 2 rides are FI so i know they're not suppose to be very quiet. Thanks again, now i'm going out to drive this amazing machine...

[OWENthatsmyname]

ha im glad i found this thread. over the winter my TIP 2.7T A6 started doing this a little, but would go away. its not doing it as much now that its warmer, but its still there a bit