wastegate noises? UrS4 - Page 2

badal · 20-11-12, 10:42 PM

Quote:

Originally Posted by quattrokid

right you techy types....

what symptoms would you get if the wastegate wasnt right?

i have what can be described as a distant foghorn kind of noise when I accelerate in Suzi, it sounds like air is blowing back past something as if its resonating,

a) could it be the diaphram
b) " " wastegate piston
c) carbon canister has a non return valve in it

turbo picks up ok and pulls hard enough but pulling away it sounds like a big hoover sucking although there are no boost leaks as thats been checked :thumbup:

suggestions please .. how easy is it to swap a complete wastegate?

could it be the D.V valve?

Nah Rich - You've had another bowl of Sprouts!

Tonks4x4 · 21-11-12, 12:17 AM

I will try and record the noise on the LWB also this weekend, I have a similar anomaly..... Sounds a bit like an orca whale....

With regards to your pm one thing for you to check is the concertina steel hose from the wastegate to the downpipe.

If this has been off it can be re fitted the wrong way round.

There is a very small arrow stamped on one end to indicate the flow of exhaust gas.

This could be one cause.

quattrokid · 21-11-12, 01:32 AM

Cheers Tonks, I'll check tmw, the turbo has been replaced so that's a possibility there

Cheers Badal

Edit

I have checked the concertina section and the arrow is pointing down the downpipes so at least that's on correctly

WOT · 21-11-12, 08:46 PM

The recirc valve is quite easy to check by blowing into each of the ports. 15minutes DIY job (assuming everything comes apart).

Maybe the N75 or one of it's connections?

quattrokid · 21-11-12, 09:43 PM

Hi Wot

N75 valve thingy was replaced with a heavy duty one

Where is the recirc valve please

is that the thing near the DV valve by the turbo ?

WOT · 21-11-12, 09:52 PM

http://www.classic-audi.co.uk/forum/...ad.php?t=24522 a few photos here

Recirc = DV by a different name i think.

Would you be prepared to try switching back in a standard N75.

Also you have an old wastegate, it could be damaged inside but i'd be inclined to check all the normal stuff first, loose hoses an connections etc.

quattrokid · 21-11-12, 10:14 PM

No I don't have a spare N75 or waste gate,

Spink has had a really good check over it but is stumped as to what the noise is or where it's coming from... to be fair Spink has really given my car a thorough make over recently.
An idea could be the non return valve in the carbon canister so Spink has 1 lined up for me which my brother in law will hopefully bring up next month.

The DV has been changed as well

spink · 21-11-12, 10:19 PM

Defo isn't drivetrain or exhaust.one thing I did mean to check (but didnt due to the other 101 things to do )were the vac pipes and valve/s associated with the air con that go through the bulkhead behind the wastegate.apart from the intermittent bagpipe sound there is also a constant quiet drone at idle(possibly when driving as well,can't remember now).i was hoping when the old box and tqc were binned it would eliminate the sound but sadly not

badal · 21-11-12, 10:23 PM

Rich

If you need garage space while you sort the problem, let me know and I'll come over and take the RS4 off your hands to give you some room to work

quattrokid · 21-11-12, 10:28 PM

Cheers Al !!!

You can fix it then for its mot then it can be driven to yours

Suzi is 99.9% perfect, just this bloody droney noise and no it's not my wife!!

At least I have all my gears and works as it should now

21-11-12, 12:17 AM	#12
Tonks4x4 4 ring whore! Classic Audi Club Member Join Date: Oct 2008 Location: Huthwaite, Nottinghamshire Posts: 2,607	I will try and record the noise on the LWB also this weekend, I have a similar anomaly..... Sounds a bit like an orca whale.... With regards to your pm one thing for you to check is the concertina steel hose from the wastegate to the downpipe. If this has been off it can be re fitted the wrong way round. There is a very small arrow stamped on one end to indicate the flow of exhaust gas. This could be one cause. __________________ http://www.tonks4x4.com

21-11-12, 01:32 AM	#13
quattrokid 4 ring whore! Classic Audi Club Member Join Date: Nov 2007 Location: Ayrshire Posts: 9,654	Cheers Tonks, I'll check tmw, the turbo has been replaced so that's a possibility there Cheers Badal Edit I have checked the concertina section and the arrow is pointing down the downpipes so at least that's on correctly __________________ RS4 B5 (wife's / ours now ) S3 8L Imola Yellow S3 8L Nogaro blue UrWR SOLD UrS4 saloon (SOLD again) S4 Cabrio (SOLD) A4 cabrio 2.5 V6tdi (SOLD) 80 cabrio 2.6 V6 SOLD 90 quattro 10v SOLD 100 2.2e SOLD FOUNDING MEMBER the 200,000 Plus miles Club

21-11-12, 09:43 PM	#15
quattrokid 4 ring whore! Classic Audi Club Member Join Date: Nov 2007 Location: Ayrshire Posts: 9,654	Hi Wot N75 valve thingy was replaced with a heavy duty one Where is the recirc valve please is that the thing near the DV valve by the turbo ? __________________ RS4 B5 (wife's / ours now ) S3 8L Imola Yellow S3 8L Nogaro blue UrWR SOLD UrS4 saloon (SOLD again) S4 Cabrio (SOLD) A4 cabrio 2.5 V6tdi (SOLD) 80 cabrio 2.6 V6 SOLD 90 quattro 10v SOLD 100 2.2e SOLD FOUNDING MEMBER the 200,000 Plus miles Club

21-11-12, 10:14 PM	#17
quattrokid 4 ring whore! Classic Audi Club Member Join Date: Nov 2007 Location: Ayrshire Posts: 9,654	No I don't have a spare N75 or waste gate, Spink has had a really good check over it but is stumped as to what the noise is or where it's coming from... to be fair Spink has really given my car a thorough make over recently. An idea could be the non return valve in the carbon canister so Spink has 1 lined up for me which my brother in law will hopefully bring up next month. The DV has been changed as well __________________ RS4 B5 (wife's / ours now ) S3 8L Imola Yellow S3 8L Nogaro blue UrWR SOLD UrS4 saloon (SOLD again) S4 Cabrio (SOLD) A4 cabrio 2.5 V6tdi (SOLD) 80 cabrio 2.6 V6 SOLD 90 quattro 10v SOLD 100 2.2e SOLD FOUNDING MEMBER the 200,000 Plus miles Club

21-11-12, 10:28 PM	#20
quattrokid 4 ring whore! Classic Audi Club Member Join Date: Nov 2007 Location: Ayrshire Posts: 9,654	Cheers Al !!! You can fix it then for its mot then it can be driven to yours Suzi is 99.9% perfect, just this bloody droney noise and no it's not my wife!! At least I have all my gears and works as it should now __________________ RS4 B5 (wife's / ours now ) S3 8L Imola Yellow S3 8L Nogaro blue UrWR SOLD UrS4 saloon (SOLD again) S4 Cabrio (SOLD) A4 cabrio 2.5 V6tdi (SOLD) 80 cabrio 2.6 V6 SOLD 90 quattro 10v SOLD 100 2.2e SOLD FOUNDING MEMBER the 200,000 Plus miles Club

21-11-12, 08:46 PM	#14
WOT Grown up member Classic Audi Club Member Join Date: Mar 2012 Posts: 119	The recirc valve is quite easy to check by blowing into each of the ports. 15minutes DIY job (assuming everything comes apart). Maybe the N75 or one of it's connections?

21-11-12, 09:52 PM	#16
WOT Grown up member Classic Audi Club Member Join Date: Mar 2012 Posts: 119	http://www.classic-audi.co.uk/forum/...ad.php?t=24522 a few photos here Recirc = DV by a different name i think. Would you be prepared to try switching back in a standard N75. Also you have an old wastegate, it could be damaged inside but i'd be inclined to check all the normal stuff first, loose hoses an connections etc.

21-11-12, 10:19 PM	#18
spink Senior Member Classic Audi Club Member Join Date: Dec 2007 Location: yorkshire Posts: 1,525	Defo isn't drivetrain or exhaust.one thing I did mean to check (but didnt due to the other 101 things to do )were the vac pipes and valve/s associated with the air con that go through the bulkhead behind the wastegate.apart from the intermittent bagpipe sound there is also a constant quiet drone at idle(possibly when driving as well,can't remember now).i was hoping when the old box and tqc were binned it would eliminate the sound but sadly not

21-11-12, 10:23 PM	#19
badal Grown up member Join Date: Jul 2008 Posts: 87	Rich If you need garage space while you sort the problem, let me know and I'll come over and take the RS4 off your hands to give you some room to work