S3 revving on its own when idle, and high pitch whistle when driving

ApolloS3

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As in the title, my S3 suddenly started making one hell of a whistle noise when driving this morning, down the motorway, its so loud i can hear it from inside. when its at ~1000-3000 revs its most frequent.

When i get to my destination, and put it into neutral (or just depress the clutch), it starts doing this...
(annoying kid on trampoline in background in case your wondering what the other sound is)


Under the bonnet...



Also worth noting the noise about 4 seconds after starting the engine, and 4 seconds after switching off...

Some friends and most internet diagnosis is looking towards the PCV valve and / or hose, or fuel pressure sensor.

It is booked in for a major service and cambelt change, however this only started happening today, on the way to a quick KFC lunch...

As im looking at around £700 for cambelt + service, I could do without another big hole in my pocket.

Thanks for any help,

Jordan

EDIT*** Ive lost a good litre of oil in about 2 weeks... ive read that if the PCV valve is broken, it forces oil out and causes oil leaks?
 
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Some friends and most internet diagnosis is looking towards the PCV valve and / or hose, or fuel pressure sensor.

It is booked in for a major service and cambelt change, however this only started happening today, on the way to a quick KFC lunch...

As im looking at around £700 for cambelt + service, I could do without another big hole in my pocket.

Thanks for any help,

Jordan

EDIT*** Ive lost a good litre of oil in about 2 weeks... ive read that if the PCV valve is broken, it forces oil out and causes oil leaks?

Also you can change the PCV yourself, I think its about £40 and easy peasy to do. Airbox off, take off the old one, give the pipes a flush with petrol a bit of oil on the gasket and pop the new one on:

Pcv

Your revs do look PCV-ish, does it settle down at all? The whine could be your belt screeching ... if it's due its change get it done ASAP!
Other than that the garage can fit you a new PCV cheapy-cheap. Cheap part, quick job.

This is only based on my experience with my PCV going, other people will know better :)
 
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Just seen this on youtube, identical problem:



Yea just get the garage to do it when they do your belt (which id be more concerned about). Its a 10 min job really and £40 part.

Sounds like a cat puuurring that vid.
 
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Update: Just in case anyone else searching gets the same issues and finds this thread: Changed the PCV valve to the newer revision (next one up from mine) and the problem is completely fixed, no erratic idle, no auto revving, no squeal and no whistle when driving.

The car also feels incredibly more powerful, its like some life has been put back into it, very happy for a cheap £40 fix, the PCV must have been on its way out for a few months now.
 
yes, pcv is really weak point on these engines. but at least it's a cheaper fix.
 
I had this on my TDI was turbo outlet hose has a minuscule hole in it so get boost leak test done for peace of mind
 
Anyone know the PCV part no.?
Just tried to order one from Audi but the guy was as much use as a handbrake in a canoe, so i'm not sure he's got me the right bit coming. 06F129101N is what i've got coming?
BTW my car is a Oct '08 S3
 
Have found that is the correct part no. above for anyone who wants to know.
Also found that if your oil filler cap isn't done up correctly - 1/4 turn instead of 1/2 turn it will provide these symptoms. Thank god for Audi-sport.net would have been an embarrasing garage visit. lol
 
Anyone know the PCV part no.?
Just tried to order one from Audi but the guy was as much use as a handbrake in a canoe, so i'm not sure he's got me the right bit coming. 06F129101N is what i've got coming?
BTW my car is a Oct '08 S3

I just had to say Thanks for all your info in this thread.
I just bought my 2009 Audi S3 last Wednesday and I absolutely love it, but after having it for less than a week, I started getting the erratic idling problems.
I was considering taking it back to the Garage, then I though let's have a quick Google search first and this thread came up.
So I called my local Audi parts depot and gave them the part number from your post, they confirmed it was the right one for my car and they had it in stock.
I picked it up today and swapped it over myself in less than 15 mins, my car now runs like a dream.

Thanks again,

Steve