Brake servo assistance - or lack of it

4.2 V8 40v biturbo - 450 bhp
4.2 V8 40v biturbo - 480 bhp (plus)
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norwichphoto
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Re: Brake servo assistance - or lack of it

Post by norwichphoto » Mon Nov 13, 2023 6:34 pm

Autodoc have delivered. Part looks right, but will compare properly shortly.

Nothings stopping me now...
Everyday: 2003 Audi RS6 C5 Saloon in Avus Silver, with black leather upholstery (for sale)
Fun: 1977 Lancia Montecarlo Evoluzione track car. (wife approves)
Wife: RenaultSport Clio RS200
Previously: Toyota Seras (several), TVR Chimaera 400, Mercedes Benz C43 AMG, Toyota Altezza RS200 etc.,

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norwichphoto
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Re: Brake servo assistance - or lack of it

Post by norwichphoto » Fri Nov 17, 2023 6:43 pm

The weather was nice this afternoon, so I fitted the new electric water pump. It appeared to be a perfect match, so hopefully that problem is solved. I then refitted the inlet manifold back to the car, and nipped up the fasteners. Note to whoever does this job in the future, the gaskets are not symettrical, if you are not careful you'll find that some of the screw holes are covered by the gasket.

Hopefully tomorrow I can continue and get a lot of the stuff re-attached.
Everyday: 2003 Audi RS6 C5 Saloon in Avus Silver, with black leather upholstery (for sale)
Fun: 1977 Lancia Montecarlo Evoluzione track car. (wife approves)
Wife: RenaultSport Clio RS200
Previously: Toyota Seras (several), TVR Chimaera 400, Mercedes Benz C43 AMG, Toyota Altezza RS200 etc.,

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Shoppinit
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Re: Brake servo assistance - or lack of it

Post by Shoppinit » Fri Nov 17, 2023 6:50 pm

:thumbs: Let us know how it goes. If you can take photos that would be cool.
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 | XC90 (V8, natch) | Passat GTE | RR Classic V8 flapper
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair."

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norwichphoto
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Re: Brake servo assistance - or lack of it

Post by norwichphoto » Sat Dec 02, 2023 11:02 pm

Well - after being able to work weekends, and in daylight only, and having a few prior engagements, job is finally done.

I could have done it much faster if I was working indoors - it was -1 most of today, but I wanted to take my time. Brake pedal feels good and idle is smooth.

I'm going to annotate the Elsawin guide with additional notes and comments.
Everyday: 2003 Audi RS6 C5 Saloon in Avus Silver, with black leather upholstery (for sale)
Fun: 1977 Lancia Montecarlo Evoluzione track car. (wife approves)
Wife: RenaultSport Clio RS200
Previously: Toyota Seras (several), TVR Chimaera 400, Mercedes Benz C43 AMG, Toyota Altezza RS200 etc.,

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Shoppinit
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Re: Brake servo assistance - or lack of it

Post by Shoppinit » Sun Dec 03, 2023 8:33 am

Great news. Look forward to seeing it.
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 | XC90 (V8, natch) | Passat GTE | RR Classic V8 flapper
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair."

Felix2566
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Re: Brake servo assistance - or lack of it

Post by Felix2566 » Sun Dec 03, 2023 9:37 pm

Brilliant, glad it seems to have fixed it!

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norwichphoto
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Re: Brake servo assistance - or lack of it

Post by norwichphoto » Tue Dec 05, 2023 5:35 pm

I took the car for a 20 minute test drive and have the following gremlins to find and evict.

- yellow brake warning light - which I think is either brake pad thickness warning or brake fluid level . Both are fine, so its a wiring glitch somewhere.

- central locking system has stopped working, both remote and with actual key. key fob battery has good voltage.

- interior light courtesy light function stopped working

- throttle feels as if it needs recalibrating.

- a/c now coming on as economy mode only. Wasn't before.
Everyday: 2003 Audi RS6 C5 Saloon in Avus Silver, with black leather upholstery (for sale)
Fun: 1977 Lancia Montecarlo Evoluzione track car. (wife approves)
Wife: RenaultSport Clio RS200
Previously: Toyota Seras (several), TVR Chimaera 400, Mercedes Benz C43 AMG, Toyota Altezza RS200 etc.,

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Shoppinit
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Re: Brake servo assistance - or lack of it

Post by Shoppinit » Wed Dec 06, 2023 8:20 am

Sounds like your comfort module is on the fritz. Maybe start by checking the fuses and seeing if you can communicate with it with the Vagcom. CHeck for water ingress under the front carpets.

For the brake warning light, should be straightforward to find.

The last two points will require some investigation. Check you didn't disconnect your high pressure switch for the AC accidentally. For the throttle, sounds like the car's not developing power properly. You should check the MAF readings and requested and achieved boost.

Or the last two could be linked. The AC won't come on if the engine thinks the conditions aren't right - overheating, etc.
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 | XC90 (V8, natch) | Passat GTE | RR Classic V8 flapper
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair."

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norwichphoto
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Re: Brake servo assistance - or lack of it

Post by norwichphoto » Wed Dec 06, 2023 11:56 am

Will be checking fuses to see if the central locking and interior lights. I think they share a common fuse.

A/C - I'm hoping I forgot to plug it back in or it didn't make proper contact. even if it means dismantling front again :bash:
Everyday: 2003 Audi RS6 C5 Saloon in Avus Silver, with black leather upholstery (for sale)
Fun: 1977 Lancia Montecarlo Evoluzione track car. (wife approves)
Wife: RenaultSport Clio RS200
Previously: Toyota Seras (several), TVR Chimaera 400, Mercedes Benz C43 AMG, Toyota Altezza RS200 etc.,

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Shoppinit
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Re: Brake servo assistance - or lack of it

Post by Shoppinit » Wed Dec 06, 2023 12:01 pm

The comfort control module does both the locking and the lights.
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 | XC90 (V8, natch) | Passat GTE | RR Classic V8 flapper
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair."

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norwichphoto
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Re: Brake servo assistance - or lack of it

Post by norwichphoto » Wed Dec 06, 2023 6:32 pm

Carpet in passenger side is dry, although that doesn't necessarily mean anything.
Everyday: 2003 Audi RS6 C5 Saloon in Avus Silver, with black leather upholstery (for sale)
Fun: 1977 Lancia Montecarlo Evoluzione track car. (wife approves)
Wife: RenaultSport Clio RS200
Previously: Toyota Seras (several), TVR Chimaera 400, Mercedes Benz C43 AMG, Toyota Altezza RS200 etc.,

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Shoppinit
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Re: Brake servo assistance - or lack of it

Post by Shoppinit » Wed Dec 06, 2023 7:48 pm

Yeah. The sound proofing is bonkers thick. You need to lift it up and feel underneath.
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 | XC90 (V8, natch) | Passat GTE | RR Classic V8 flapper
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair."

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norwichphoto
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Re: Brake servo assistance - or lack of it

Post by norwichphoto » Thu Dec 07, 2023 10:37 pm

The throttle calibration is more of a low speed thing. It feels as if its wanting to pull slightly at low revs. Almost akin to over enthusiastic 'creep' from an automatic gearbox. Engine cooling appears to be normal - its getting hot, heater's producing heat. Coolant level is fine.

Unless this is correct, and previously I had a minor vacuum leak and didn't know.
Everyday: 2003 Audi RS6 C5 Saloon in Avus Silver, with black leather upholstery (for sale)
Fun: 1977 Lancia Montecarlo Evoluzione track car. (wife approves)
Wife: RenaultSport Clio RS200
Previously: Toyota Seras (several), TVR Chimaera 400, Mercedes Benz C43 AMG, Toyota Altezza RS200 etc.,

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norwichphoto
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Re: Brake servo assistance - or lack of it

Post by norwichphoto » Sat Dec 09, 2023 7:32 pm

Today.
- a/c system seems to have fixed itself.

- couldn't see anything wrong with the brake pad warning wiring - plenty of pad material. No visible damage to the wiring.

- Ground off the knobbly bits with a battery powered angle grinder, then neatened up with Dremel.

- Comfort module is totally dry - pulled up carpet enough to feel for moisture.

- Courtesy lights seem to be fixing themselves.

- Going to recode key fobs to car to see if that works.
Everyday: 2003 Audi RS6 C5 Saloon in Avus Silver, with black leather upholstery (for sale)
Fun: 1977 Lancia Montecarlo Evoluzione track car. (wife approves)
Wife: RenaultSport Clio RS200
Previously: Toyota Seras (several), TVR Chimaera 400, Mercedes Benz C43 AMG, Toyota Altezza RS200 etc.,

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Shoppinit
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Re: Brake servo assistance - or lack of it

Post by Shoppinit » Sat Dec 09, 2023 7:34 pm

You might need to delete the existing ones with the Vagcom before learning new ones. Sometimes the comfort module is a bit thick.
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 | XC90 (V8, natch) | Passat GTE | RR Classic V8 flapper
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair."

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