A8 Parts Forum  

Go Back   A8 Parts Forum > A8 D2 > D2 - Common Faults

D2 - Common Faults Quick links to all known common faults and their solutions

Reply
 
Thread Tools Display Modes
  #1  
Old 2nd September 2017, 02:52 PM
moltuae's Avatar
moltuae moltuae is offline
Senior Member
 
Join Date: Sep 2014
Location: East Lancs.
Posts: 2,087
Default Service (and repairs) time ...

Service is due so I'm hoping to get it booked into the garage next week ...

I've got a few faults/issues that I'm looking to get fixed while it's in too. Has anyone got any advice or technical info on any of these faults/symptoms that I can pass on to the garage?


Firstly, I'm getting a creaking when pressing the brake pedal (whether moving or stationary) that seems to be coming from the o/s/f calliper. Is this common and likely to be a calliper fault?



Secondly, I have an intermittent ABS/ESP issue that is recording the following fault code:

Quote:
03 Brakes

System description: ABS/ESP allrad D57
Software number: 4D0907389E
Coding: 08397

Trouble codes:
01423 - Lateral acceleration sensor Implausible signal
Intermittent
Is this likely to be a faulty G200 sensor and does anyone have any info such as part numbers and location? (I can't find it in any of the 'tech dump' documents).


Thirdly, I've had a whirring noise for a while that's engine-speed related (starts about 2000rpm and gets higher pitched with increasing rpm). The garage had a brief look at it when it first occurred but suggested that I "let it develop". They suspected the bearings in the alternator and/or the PS pump. The noise hasn't got any louder in the past few months but I'd like to get it fixed now. Is there any simple way to determine where the noise is coming from?


Lastly, I seem to have a bit of front bumper droop. I noticed a while ago that it didn't seem to look quite right. Studying the recent Carding Shed photos (see attached), using Jim's car for comparison, there's clearly a gap that shouldn't be there. Has it been refitted incorrectly or is there some way to adjust it?
Attached Thumbnails
Click image for larger version

Name:	front-bumper-gap.jpg
Views:	49
Size:	232.9 KB
ID:	16935  
__________________
Mark
------------------------------------------------------
2002 FE S8 Ebony Black Pearl
------------------------------------------------------

------------------------------------------------------
Cars Owned:

The Audi Era: '97 A8 4.2 (Ming Blue) --> '96 A8 4.2 QS (Dark Green) --> '02 FE S8 (present)
The Citroen Era: '84 BX 1.6 RS --> '89 BX 1.9 DTR Turbo --> '94 XM 2.0L Turbo --> '96 XM 2.0L Turbo Exclusive --> '00 Xantia Activa 2.0L Turbo
The Banger Era: '76 1.2L Lada VAZ-2101 (Ruski Fiat 124) --> '80 1.7L Morris Ital HL, finished in Ermine White and Rust

Last edited by moltuae; 2nd September 2017 at 02:57 PM.
Reply With Quote
  #2  
Old 2nd September 2017, 04:22 PM
MikkiJayne MikkiJayne is offline
Senior Member
 
Join Date: Jan 2012
Location: Devon
Posts: 1,880
Default

Quote:
Originally Posted by moltuae View Post
Firstly, I'm getting a creaking when pressing the brake pedal (whether moving or stationary) that seems to be coming from the o/s/f calliper. Is this common and likely to be a calliper fault?
The pads are probably stuck in the caliper. Pull them out, clean up & grease the sliding surfaces and see what happens.


Quote:
Originally Posted by moltuae
Secondly, I have an intermittent ABS/ESP issue that is recording the following fault code:

Is this likely to be a faulty G200 sensor and does anyone have any info such as part numbers and location? (I can't find it in any of the 'tech dump' documents).
Possibly although its worth checking if the carpet is damp. Its under the carpet under the passenger seat. I'll try and find a number later.

Quote:
Originally Posted by moltuae
Thirdly, I've had a whirring noise for a while that's engine-speed related (starts about 2000rpm and gets higher pitched with increasing rpm). The garage had a brief look at it when it first occurred but suggested that I "let it develop". They suspected the bearings in the alternator and/or the PS pump. The noise hasn't got any louder in the past few months but I'd like to get it fixed now. Is there any simple way to determine where the noise is coming from?
If its the P/S pump the sound will change as you rock the steering. If the noise doesn't change with steering its more likely to be one of the rollers on the front end rather than the alternator. There's an idler, the main tensioner and the viscous fan which can all get noisy. I'd pop the belt off (put the front end in service position) and spin them all by hand and see if any are rough or noisy.

Quote:
Originally Posted by moltuae
Lastly, I seem to have a bit of front bumper droop. I noticed a while ago that it didn't seem to look quite right. Studying the recent Carding Shed photos (see attached), using Jim's car for comparison, there's clearly a gap that shouldn't be there. Has it been refitted incorrectly or is there some way to adjust it?
The two main bumper supports have threaded inserts in them to adjust the height of the bumper, but their position relative to the car is lost whenever you pull the front end off so they usually need adjusting every time it comes apart. If you're putting it in service position to look at the accessory drive then it can all be adjusted when it goes back together. Its designed to be highly adjustable so the factory can get the front end perfect, but its a right pain to get it back in the right place again every time it has any major work done!
__________________


facebook.com/D2Doctor
Reply With Quote
  #3  
Old 2nd September 2017, 08:08 PM
moltuae's Avatar
moltuae moltuae is offline
Senior Member
 
Join Date: Sep 2014
Location: East Lancs.
Posts: 2,087
Default

Brilliant!

Thanks very much MJ!
__________________
Mark
------------------------------------------------------
2002 FE S8 Ebony Black Pearl
------------------------------------------------------

------------------------------------------------------
Cars Owned:

The Audi Era: '97 A8 4.2 (Ming Blue) --> '96 A8 4.2 QS (Dark Green) --> '02 FE S8 (present)
The Citroen Era: '84 BX 1.6 RS --> '89 BX 1.9 DTR Turbo --> '94 XM 2.0L Turbo --> '96 XM 2.0L Turbo Exclusive --> '00 Xantia Activa 2.0L Turbo
The Banger Era: '76 1.2L Lada VAZ-2101 (Ruski Fiat 124) --> '80 1.7L Morris Ital HL, finished in Ermine White and Rust
Reply With Quote
  #4  
Old 2nd September 2017, 08:22 PM
Goran's Avatar
Goran Goran is offline
Senior Member
 
Join Date: Feb 2011
Posts: 1,995
Default

My breaks creak a bit too, I suspect the front calipers, even though they were re-conditioned a couple of years ago. No ill effect so far. Although I will try re-greasing them too as MJ suggests.
Reply With Quote
  #5  
Old 2nd September 2017, 08:46 PM
MikkiJayne MikkiJayne is offline
Senior Member
 
Join Date: Jan 2012
Location: Devon
Posts: 1,880
Default

The S8 I have in at the moment came in to the workshop with the brakes almost on fire. Turns out the inner pads were jammed solid in the calipers and only the outer pad was moving, caused by rust on the edge of the pad backing plate, plus dirt and brake dust building up on the caliper. The calipers on this one were reconditioned a couple of years ago, but the Brembos are a flawed design in that regard as the clearances are so tight. I pull the pads and clean everything up every oil change which stops them getting stuck

(I also pull and re-grease the front strut pinch bolt every oil change too )
__________________


facebook.com/D2Doctor
Reply With Quote
  #6  
Old 2nd September 2017, 09:40 PM
David's8's Avatar
David's8 David's8 is offline
Senior Member
 
Join Date: Jan 2012
Location: Helensburgh, Scotland
Posts: 3,043
Default

MJ is always spot on with advice. The front caliper creakiness is (was, in my case) associated with the pads jamming in the stainless steel pad guides held in place on the aluminium caliper block by torx headed screw which is impossible(?) to remove without splitting the block. The corrosion between the s/steel and aluminium forces the guide outer edges which then clamp on the pads. You can do a certain amount of cleaning out the corrosion with the calipers removed using emery paper etc but its difficult to get the guides to resume their former shape. You can, of course, file down the edges of the pads so that they can fit but its not really a solution. Thats the point at which I got mine refurbished.
I suggest you test the temperature of the discs after a run to see if there is any overheating but its a certainty that wthout some work, it will develop into overheating pads/discs at some point in the near future.
__________________
2002 D2 S8 Ming Blue, Valcona leather, Vavona wood insert, solar sunroof (to be fitted), Heated rear seats, extended leather pack, 18 Avus, ski hatch, Bose, auto dim rear view mirror, rear blind.
Reply With Quote
  #7  
Old 3rd September 2017, 10:44 AM
Goran's Avatar
Goran Goran is offline
Senior Member
 
Join Date: Feb 2011
Posts: 1,995
Default

Thanks, definitely need to look into it then. I often check the disc temperature after a drive after one of the rears jammed on my previous S8. On this one so far no excess heat, just creaking. I guess the ultimate solution is a front brake upgrade lol.
Reply With Quote
  #8  
Old 3rd September 2017, 02:34 PM
moltuae's Avatar
moltuae moltuae is offline
Senior Member
 
Join Date: Sep 2014
Location: East Lancs.
Posts: 2,087
Default

Quote:
Originally Posted by MikkiJayne View Post
Possibly although its worth checking if the carpet is damp. Its under the carpet under the passenger seat. I'll try and find a number later.
The carpets are bone dry now (and have been for a long time) but, like most D2 owners, I have had one or two incidences of blocked drains and water ingress over the years, so it's probably worth opening it up and giving it a clean-up and check over. That is if I can find it ...

I've just had a quick look under the seat. There seems to be something under the carpet near where the wiring loom enters. I assume that the seat and numerous bits of trim need to be removed to get to it (without resorting to slashing the carpet open)?

Quote:
Originally Posted by David's8 View Post
The front caliper creakiness is (was, in my case) associated with the pads jamming in the stainless steel pad guides held in place on the aluminium caliper block by torx headed screw which is impossible(?) to remove without splitting the block. The corrosion between the s/steel and aluminium forces the guide outer edges which then clamp on the pads. You can do a certain amount of cleaning out the corrosion with the calipers removed using emery paper etc but its difficult to get the guides to resume their former shape. You can, of course, file down the edges of the pads so that they can fit but its not really a solution. Thats the point at which I got mine refurbished.
I suggest you test the temperature of the discs after a run to see if there is any overheating but its a certainty that wthout some work, it will develop into overheating pads/discs at some point in the near future.
Thanks David

I'll ask the garage to take a look at them and see what they think. Who refurbished your callipers and what's the general consensus for the best place(s) now? I seem to remember there was some mixed experiences/reviews with some of the refurbishers. Is there one particular refurbisher who does a consistently good job?

And is there a substantial difference in price between refurbished and new (OEM)?
__________________
Mark
------------------------------------------------------
2002 FE S8 Ebony Black Pearl
------------------------------------------------------

------------------------------------------------------
Cars Owned:

The Audi Era: '97 A8 4.2 (Ming Blue) --> '96 A8 4.2 QS (Dark Green) --> '02 FE S8 (present)
The Citroen Era: '84 BX 1.6 RS --> '89 BX 1.9 DTR Turbo --> '94 XM 2.0L Turbo --> '96 XM 2.0L Turbo Exclusive --> '00 Xantia Activa 2.0L Turbo
The Banger Era: '76 1.2L Lada VAZ-2101 (Ruski Fiat 124) --> '80 1.7L Morris Ital HL, finished in Ermine White and Rust
Reply With Quote
  #9  
Old 3rd September 2017, 07:14 PM
David's8's Avatar
David's8 David's8 is offline
Senior Member
 
Join Date: Jan 2012
Location: Helensburgh, Scotland
Posts: 3,043
Default

Quote:
Originally Posted by moltuae View Post
Who refurbished your callipers and what's the general consensus for the best place(s) now? I seem to remember there was some mixed experiences/reviews with some of the refurbishers. Is there one particular refurbisher who does a consistently good job?

And is there a substantial difference in price between refurbished and new (OEM)?
I used Bigg Red for my rear caliper refurb (190 inc paint and VAT) but when i spoke to them about the front, they said that they havent the tools/expertise to split the Bembos but passed me on to Addiction Motorsport in East Ham, London who did a very good job. They split the caliper, remove and clean the pad guides and will re-use the steel pad guides if they are OK or re-manufacture new ones if too bent. They use Brembo seals as well as replacing bleed nipples with the proper coated thead OEM ones to avoid steel/alu corrosion. Not cheap at 390 but I feel that they have done a good job.
__________________
2002 D2 S8 Ming Blue, Valcona leather, Vavona wood insert, solar sunroof (to be fitted), Heated rear seats, extended leather pack, 18 Avus, ski hatch, Bose, auto dim rear view mirror, rear blind.
Reply With Quote
  #10  
Old 3rd September 2017, 11:51 PM
Architex_mA8tey's Avatar
Architex_mA8tey Architex_mA8tey is offline
Moderator
 
Join Date: Jan 2009
Location: London/Oxford/Swindon
Posts: 7,302
Default

if the side bumper brackets arent loose / havent moved the it may be that at some point you have caught the bottom lip on a surface which has caused one of the small plastic sliders that the bumper slides on to to break off, partly or completely - this would result in the same issue. New brackets from memory will be between 10 and 20 each so not too expensive if they are damaged
__________________

Confidence is the feeling you have before you know better . . . .
Audi A8 D2 3.7 Quattro Sport 1999 FL - Melange
20" x 9" Bentley GTC Wheels with 385mm W12 Front Discs & Bentley Caliper Covers, Front Lowered on Coilovers, Xenons, Combined DRLs and LED Foglights to modified OEM front fog lamp position, Alcantara/Leather, Full Black Alcantara headlining + pillars and blind shelf, Bespoke Flat Bottomed Sports Steering Wheel, Dark Myrtle Wood, Autodim Mirrors, Bose, Blinds, Digital TV, Ski Hatch, Modified rear exhaust section for extra V8 Burble
Next - Clean Car, Phantom Aeriel, Clean Car again, Fit Variable Back Box with remote control on/off Loudness, RNS-e, Clean Car again!
Audi A8L D3 4.2 Petrol with LPG - Oyster Grey
and some other A8's A8L's and Mercs
Reply With Quote
Reply

Thread Tools
Display Modes

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 Off

Forum Jump


All times are GMT. The time now is 05:04 AM.


Powered by vBulletin® Version 3.8.0
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.