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  #31  
Old 21st July 2018, 05:21 PM
ainarssems ainarssems is offline
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It could well be the culprit and no it does not show up on VCDS or at least not on PF. My S8 was heating up to 120C and slowly loosing coolant through the cap couple of years ago in slow traffic. It turned out that electrical fan had failed and valve was stuck in coolant reservoir cap letting the pressure and coolant to escape when getting too hot. Second hand fan and new Febi cap later normal service was resumed.
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  #32  
Old 21st July 2018, 06:10 PM
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The_Laird The_Laird is offline
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Thanks Ainars. Is it the fan motor that fails? And should i be able to see it running at normal operating temperatures?
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2002 Final Edition S8. Ebony black with Silver Grey leather and myrtle wood trim.
Current mods: solar sun roof, 20mm rear spacers, 15 mm on front, red brembo callipers, 6k headlights, rear view camera, engine remap, alloy dash dial rings, alloy navi rings, tt/phaeton pedal upgrade, (and custom matching foot rest) dension ipod interface & parrot hands free kit (both fully hidden), av input, tv in motion switched thro' PF switch in blanking plug right of steering column, Audi 'quattro' sill covers, repositioned centre console switches, radio clock, .
Planned mods: auto-dimming rear view mirror, dash cam (as steamship's), fit the ski hatch, refit philips drl's (or maybe not - nope, definitely not - horrible botch!).
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  #33  
Old 21st July 2018, 07:58 PM
MikkiJayne MikkiJayne is offline
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Usually the motor seizes up and pops the fuse. It should come on with the AC.
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  #34  
Old 21st July 2018, 08:28 PM
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The_Laird The_Laird is offline
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Quote:
Originally Posted by MikkiJayne View Post
Usually the motor seizes up and pops the fuse. It should come on with the AC.
Thanks MJ. Does it have it’s own fuse? And, if the air con (AC?) is on, should the fan be running?
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2002 Final Edition S8. Ebony black with Silver Grey leather and myrtle wood trim.
Current mods: solar sun roof, 20mm rear spacers, 15 mm on front, red brembo callipers, 6k headlights, rear view camera, engine remap, alloy dash dial rings, alloy navi rings, tt/phaeton pedal upgrade, (and custom matching foot rest) dension ipod interface & parrot hands free kit (both fully hidden), av input, tv in motion switched thro' PF switch in blanking plug right of steering column, Audi 'quattro' sill covers, repositioned centre console switches, radio clock, .
Planned mods: auto-dimming rear view mirror, dash cam (as steamship's), fit the ski hatch, refit philips drl's (or maybe not - nope, definitely not - horrible botch!).
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  #35  
Old 21st July 2018, 08:44 PM
MikkiJayne MikkiJayne is offline
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Yes, there are three fuses - one for each speed - all in the passenger side electrics box. It should always be on the 1st speed when the AC compressor is running, ie not in 'econ' mode.
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  #36  
Old 21st July 2018, 08:49 PM
ainarssems ainarssems is offline
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Mine was not seized, just not running. IRRC it should run at slow speed if AC is on. I got replacement fairly cheaply so never investigated if it had bushes or sliprings worn out.
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  #37  
Old 23rd July 2018, 01:38 PM
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The_Laird The_Laird is offline
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Both fans are working and it’s still overheating
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2002 Final Edition S8. Ebony black with Silver Grey leather and myrtle wood trim.
Current mods: solar sun roof, 20mm rear spacers, 15 mm on front, red brembo callipers, 6k headlights, rear view camera, engine remap, alloy dash dial rings, alloy navi rings, tt/phaeton pedal upgrade, (and custom matching foot rest) dension ipod interface & parrot hands free kit (both fully hidden), av input, tv in motion switched thro' PF switch in blanking plug right of steering column, Audi 'quattro' sill covers, repositioned centre console switches, radio clock, .
Planned mods: auto-dimming rear view mirror, dash cam (as steamship's), fit the ski hatch, refit philips drl's (or maybe not - nope, definitely not - horrible botch!).
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  #38  
Old 23rd July 2018, 02:19 PM
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moltuae moltuae is offline
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Might be your viscous fan clutch, Jim. When was it last changed?

I believe you can check it by seeing how easily you can turn it by hand when the engine is hot (*without the engine running!).





*Unless you're feeling brave and/or stupid ...

https://www.youtube.com/watch?v=wEnY9oXW9PU

https://www.youtube.com/watch?v=cOXcrbQRDWU
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Cars Owned:
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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
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  #39  
Old 23rd July 2018, 02:52 PM
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The_Laird The_Laird is offline
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Quote:
Originally Posted by moltuae View Post
Might be your viscous fan clutch, Jim. When was it last changed?

I believe you can check it by seeing how easily you can turn it by hand when the engine is hot (*without the engine running!).





*Unless you're feeling brave and/or stupid ...

https://www.youtube.com/watch?v=wEnY9oXW9PU

https://www.youtube.com/watch?v=cOXcrbQRDWU
It’s never been changed since I’ve owned the car. I assume that I shouldn’t be able to turn it easily by hand?
__________________
2002 Final Edition S8. Ebony black with Silver Grey leather and myrtle wood trim.
Current mods: solar sun roof, 20mm rear spacers, 15 mm on front, red brembo callipers, 6k headlights, rear view camera, engine remap, alloy dash dial rings, alloy navi rings, tt/phaeton pedal upgrade, (and custom matching foot rest) dension ipod interface & parrot hands free kit (both fully hidden), av input, tv in motion switched thro' PF switch in blanking plug right of steering column, Audi 'quattro' sill covers, repositioned centre console switches, radio clock, .
Planned mods: auto-dimming rear view mirror, dash cam (as steamship's), fit the ski hatch, refit philips drl's (or maybe not - nope, definitely not - horrible botch!).
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  #40  
Old 23rd July 2018, 03:00 PM
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moltuae moltuae is offline
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Quote:
Originally Posted by The_Laird View Post
It’s never been changed since I’ve owned the car. I assume that I shouldn’t be able to turn it easily by hand?
If I understand correctly how it works, you should be able to turn it fairly easy by hand when the clutch is cold but the turning resistance should increase as it heats up.

They do tend to fail/wear out I believe. I usually have mine replaced at every major service. I should have the last one that was replaced here somewhere, which was working when it was removed. You're welcome to have it if it turns out to be that, although it might make more economical sense to fit a new one.
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2002 FE S8 Ebony Black Pearl
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Cars Owned:
The Tesla Era: 2020 Model S Performance Ludicrous+ (present)
(Black, with all black premium interior and carbon fibre décor, 21" sonic carbon twin turbine wheels and FSD capability)

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
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