Go Back   AudiWorld Forums > Audi Models > Audi S4 / RS4 > S4 / RS4 (B5 Platform) Discussion
Sign in using an external account
Register Forgot Password?


S4 / RS4 (B5 Platform) Discussion Discussion forum for the B5 Audi S4 & RS4 produced from 1998-2002

4 signs of bad turbos that I've personally witnessed...maybe it'll kill some paranoia, or make

Reply
 
 
 
 
LinkBack Thread Tools Search this Thread
Old 04-24-2002, 05:50 AM   #1
Banned
Account #: 21977
 
Join Date: Jul 2001
Posts: 19,472
Default 4 signs of bad turbos that I've personally witnessed...maybe it'll kill some paranoia, or make

life even worse for ya ..note: in every case, the overall power of the car remained about the same as it built up proper boost pressure at some point throughout the revs. In cases 1 or 2, it is very noticeable while chipped and can result in the turbo(s) dying even earlier. But regardless, they'd be destroyed anyway under the stock chip. The first two cases have been due to the impeller shaft warpage.

1. Higher pitch than normal turbo spooling sound. Almost sounds similar to a high pitch dentist drill. Witnessed this on the passenger side turbo.

2. An in-and-out wailing type sound of the turbos spooling. Very noticeable while chipped. Witnessed this on the passenger side turbo.

3. Major amounts of oil leaking into the intake side. Witnessed this on the driver's side turbo in two cases.

4. A very inconsistent dyno plot. Power and torque are built later in the rpm range(typically around 500 rpm+), and then they both die off earlier and much more rapidly as the revs max out (typically around 5k rpm).

One of the best ways to diagnose this has been to plot boost pressure versus rpm for the particular engine computer and then compare it to a healthy car. I looked into checking actual versus requested boost, but this has not shown anything. My friend and I were talking last night, and you'd think that the ECU would recognize that the boost is not building according to when it was desired and you'd want to set a fault code. Oh well...didn't/doesn't happen.

hope the descriptions helped a bit...here's a typical case...green is good (notice how the boost comes in earlier) while blue is bad (boost comes in late)

Mike@VAST is offline   Reply With Quote
Old 04-24-2002, 05:54 AM   #2
Elder Member
Account #: 13456
 
Join Date: Dec 2000
Posts: 12,498
Default welcome back.

btw PAWHN STAH ins't sure about his yet...do you think blow by/back could be the cause of oil in the TBB area? that was brought up a couple times...think donp has it too.
BiturboBoy_V2.0_S3-- is offline   Reply With Quote
Old 04-24-2002, 05:56 AM   #3
Elder Member
Account #: 189
 
Join Date: Mar 2000
Posts: 15,750
Default I always tell people, in regards to the sounds, if you have any doubt, its not blown...

You know the real siren sound when you hear it, and you absolutely know the high pitched whine of a dead turbo.

Its not an absolute rule, but it stops a lot of panic when people realize that most of the sounds they hear are normal.
__________________


Boston Audi Group Website
George @ BostonAudi is offline   Reply With Quote
Old 04-24-2002, 05:59 AM   #4
Banned
Account #: 21977
 
Join Date: Jul 2001
Posts: 19,472
Default thanks...the blow by is different...in Ant's case, we couldn't trace the

oil from the two lines tapped into the intake on or near the y-pipe. Has he pulled the lower turbo air outlet line yet (right before the IC inlet)? Pull that and I bet it's nasty.

AS far as the oil lines to the turbos themselves leaking, this has been a problem before.

I haven't seen any coolant problems yet.
Mike@VAST is offline   Reply With Quote
Old 04-24-2002, 06:01 AM   #5
Banned
Account #: 21977
 
Join Date: Jul 2001
Posts: 19,472
Default yeah, like that normal higher pitched spin sound when the motor is cold.

Mike@VAST is offline   Reply With Quote
Old 04-24-2002, 06:09 AM   #6
New Member
Account #: 9265
 
Join Date: Aug 2000
Posts: 211
Default question for you - do you have the miltek turbo back exhaust?

I seem to remember that you posted about a CE light with this system. I have the miltek and am getting the catalyst inefficency CE pretty consistently now - where I never experienced this last year. How did you fix this or are you going to live with it?
cs22 is offline   Reply With Quote
Old 04-24-2002, 06:12 AM   #7
Elder Member
Account #: 13456
 
Join Date: Dec 2000
Posts: 12,498
Default do you mean this hose?

sorry for the smellssogood quality of my part circling! lol.

BiturboBoy_V2.0_S3-- is offline   Reply With Quote
Old 04-24-2002, 06:14 AM   #8
New Member
Account #: 23511
 
Join Date: Aug 2001
Posts: 114
Default Now Im paraniod again. Thanks alot

__________________

Im stupid
S4F3 is offline   Reply With Quote
Old 04-24-2002, 06:15 AM   #9
Banned
Account #: 21977
 
Join Date: Jul 2001
Posts: 19,472
Default yep...but, that code you are seeing is not terrible. You shouldn't be seeing a check engine

light with that code...(please correct me if I'm wrong)...it's been a while since I've seen that. That code can be set if you really push the car hard....(i believe that's how I set it before)

The DTC's I've been getting was for an O2 sensor correction factor. THis is due to either bad cats or bad O2 sensors or both. It is set when the ECU doesn't see a proper secondary O2 sensor voltage after the inline cats.
Mike@VAST is offline   Reply With Quote
Old 04-24-2002, 06:17 AM   #10
Banned
Account #: 21977
 
Join Date: Jul 2001
Posts: 19,472
Default no, the lower one to the IC (its inlet)

Mike@VAST is offline   Reply With Quote
Old 04-24-2002, 06:18 AM   #11
New Member
Account #: 30577
 
Join Date: Jan 2002
Posts: 492
Default My turbos sounded totally normal up until about 5-10 minutes before they blew.

I knew they were going to blow, I was driving with my girlfriend and I told her we would be lucky to make it home and about 2 minutes later a large cloud of smoke excited the car

I did notice a small oil leak coming from somewhere in the engine before the turho's failed, but have not found out the official cause of the failure. Will let you all know when diagnosis is done.

FYI. I was religious about letting the oil warm up to at least 150 and always did cool down.
Used 0W-30 and 0W-40 oil.
__________________

Car - Gone
New V8 Touareg Black/Teak (Business car/better write off)
MidWestTouareg is offline   Reply With Quote
Old 04-24-2002, 06:21 AM   #12
Banned
Account #: 21977
 
Join Date: Jul 2001
Posts: 19,472
Default even these people were religious about the cool down....even to the extent of

popping the hood after driving in one case

i'd be interested how yours died too ...if i could get pictures of these other cars' turbos while they were at the dealer, i would have.
Mike@VAST is offline   Reply With Quote
Old 04-24-2002, 06:22 AM   #13
New Member
Account #: 24991
 
Join Date: Sep 2001
Posts: 259
Default What about an almost metalic sounding noise along with the siren sound?...more...

This noise is a metalic spining sound that accompanies the turbos spooling. Most evident when engine is cold, but more recently I can still here it after car has warmed up. Anyone run across anything similar? TIA
__________________
4LinkS4 is offline   Reply With Quote
Old 04-24-2002, 06:25 AM   #14
Banned
Account #: 21977
 
Join Date: Jul 2001
Posts: 19,472
Default yep. that case with the wailing (siren sound as you say) has been accompanied by that metallic sound

even whilst warm
Mike@VAST is offline   Reply With Quote
Old 04-24-2002, 06:26 AM   #15
New Member
Account #: 30577
 
Join Date: Jan 2002
Posts: 492
Default Re: What about an almost metalic sounding noise along with the siren sound?...more...

Not to alarm you but that is the exact sound I had, but the car was up to full temp.
__________________

Car - Gone
New V8 Touareg Black/Teak (Business car/better write off)
MidWestTouareg is offline   Reply With Quote
Old 04-24-2002, 06:27 AM   #16
New Member
Account #: 24991
 
Join Date: Sep 2001
Posts: 259
Default So are you saying that I sould be alarmed or not?

__________________
4LinkS4 is offline   Reply With Quote
Old 04-24-2002, 06:28 AM   #17
New Member
Account #: 9265
 
Join Date: Aug 2000
Posts: 211
Default That is the only fault code I see w/ the vag - and it causes a CE light after 3-4 days.

Its strange that I would get a CE light when they never triggered a CE light last summer - and I'm sure I drove more agressively last year (new toy syndrome). So how are you fixing your situation - new cats?
cs22 is offline   Reply With Quote
Old 04-24-2002, 06:29 AM   #18
New Member
Account #: 30577
 
Join Date: Jan 2002
Posts: 492
Default I will see what I can find out from the dealer and pics if possible.

__________________

Car - Gone
New V8 Touareg Black/Teak (Business car/better write off)
MidWestTouareg is offline   Reply With Quote
Old 04-24-2002, 06:33 AM   #19
Senior Member
Account #: 24554
 
Join Date: Aug 2001
Posts: 8,611
Default punk. It's in the shop as we speak...errr type.

__________________

07 RS4 Daytona Gray/Onyx
01 S4 Brilliant Black/Onyx...
6 spd Rowing Machines.
xr8edS4 is offline   Reply With Quote
Old 04-24-2002, 06:33 AM   #20
Senior Member
Account #: 24554
 
Join Date: Aug 2001
Posts: 8,611
Default =(

__________________

07 RS4 Daytona Gray/Onyx
01 S4 Brilliant Black/Onyx...
6 spd Rowing Machines.
xr8edS4 is offline   Reply With Quote
Old 04-24-2002, 06:33 AM
AudiWorld
Audi R8




Paid Advertisement
 
 
 
Reply

Tags
a4, b5, bad, dentist, dieing, drill, dying, good, personally, s4, signs, things, turbo, turbos, witnessed


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On



Join AudiWorld

All times are GMT -8. The time now is 10:31 AM.


Copyright 2014 AudiWorld.com Audi Enthusiast Community