A 8

Hoping for some quick advice!

I am considering a 2005 W12 and took it for a test drive today...wow, I could hardly hear the engine and at the same time it was super powerful. Made me smile involuntary when pushing it a bit or maybe I should say as far as it would go
I tested a 2008 4,2 TDI just after hoping I would like it as its a more sensible choice but I am sorry to say that there is no way I am getting the TDI.
Anyway I kind of expected that but I had a tire pressure/sensor warning and going into the mmi i got nothing ie no temp, pressure on any of the tires. I also noticed a few remarks on older service records about the cigarette lighter power not working.

The dealer said that they had the tire pressure warning thing on another W12 but that it was an easy fix (I could turn it off), at the same time he gave me an offer that excluded fixing the tire sensor thing so I am getting suspicious.

So is there any particular issues with the tire sensors that I need to be aware of or is it an indication of other problems?

Also the brakes was vibrating and not as lucid as what I am used too from my old D2 A8 or as the 4.2TDI I drove just after. It felt like the pads was worn out but there was no warning.
It looked like the calipers were different from the TDI ones and the other A8's so does anyone know if there are anything particular I need to look out for wrt the brakes?

Thanks

Brozee

Your rotors are porobably toast if your experiencing vibrating. And the tpms are either working or there not. Pretty simple.

MP4.2+6.0

TPMS: See if the sensors are even there. If plain black rubber valve stems, of course they have been removed. If you see what look like silver grey nuts you could put a socket wrench on, the sensors are most likely still there. Yes, it can be disabled entirely so no warning light will show. As a 2005, it will be near the quoted 6 year ave. life of the sensor batteries if they are there and original.

Brakes: First, if it is vibrating with braking application, you might check something else--worn upper A arms in front. Somewhere between common and universal that they wear on D3's (and many other Audi's). If worn a lot, can set up vibration during braking. Otherwise, yes probably assume front rotors are warped, plus pads.

For reference, owning a 2000 A6 4.2 which has the HP2 brakes just like the D2 A8, I would give the nod to the W12 brakes by a fair margin, assuming both systems are in good shape. Thus, if the W12 isn't feeling at or above that level, may need a brake job and/or bleeding w/ fresh fluid. The HP2's are very good as a baseline, but the D3 brakes another notch up--quite a bit more pad area, much larger rotors, nicer + somewhat firmer feel to me than the HP2's. Stopping power on the HP's really good, but prone to some fade with repeated application from speed; W12 set up is borderline extreme for in terms of its sheer stopping power and speed. If it helps as a knowledge point, the W12 set up in front is similar to the D3 4.2 set up, but the rotors are larger and somewhat thicker, and the (dual) pistons in the calipers are larger. Pads are almost identical, but with the larger rotor diameter (385mm/15"+), the swept area is meaningfully greater. In the rear, the set up is essentially identical to the C5 RS6, which makes general sense given similar weight, 450HP, etc. My comparison across the cars is with 255's on the C5 4.2 and 275's on the W12--high performance summers in both cases--so the added width likely increases stopping power marginally as well.

mishar

Tire pressure sensors (5) + rotors (4) + pads (8) + labor = $2000 in North America. You can switch off TPMS but you are buying luxury car. Don't start with compromises.

Brozee

Tire rack has the rear rotors on sale for a whopping $18 a piece. That's extremely cheap.

Front Pads $140
Rear Pads $80
Front Rotors: $200-300
Rear Rotors: $18-150

TPMS; go to discount tire, and have them match tire racks price. They sell the OEM replacement. I believe I got them for $108 a piece.

s4master1

First, we are assuming is the brakes, which either way whatever it may be at this point it needs rotors.

4E0 615 301 K front rotors x2 @ 170.00 = 340.00
4E0 698 151 K front pads x1 @ 170.00 = 170.00, That's 510.00 for front parts only plus 2 hours of labor.

4E0 615 601 L rear rotors x2 @ 120.00 = 240.00
4E0 698 451 A rear pads x1 @ 80.00 That's 320.00 for the rear plus 2 hours of labor.

A8nightmare

How many miles are on the car you are looking at?

A 8

Thanks all, good info!

Its at around 55K and I have done some research today, checking service and repair history in person with the Audi reseller who originally sold the car and have since serviced it. It turns out that the wheels have been stolen so I assume the car has been left standing on the ground supported by whatever are the lowest points without the wheels!

This also makes it difficult to assess what else could have been damaged. I assume the rotors probably have some deformation which would explain the vibration but not the lack lucidity or break power I would expect (they were kind of weak and without depth)
Perhaps the calipers are large enough to hit ground without wheels in this scenario(making them uneven and not using the full area for braking power)?

This may also explain the TPMS issue, most likely the new wheels does not include the sensors but I need to check that to make sure.

I am also worried about the transmission line, anyone know if it is "low" enough to hit ground without wheels?

I really like the way the car handled and I feel there is no going back in terms of NOT getting a W12 if I were to change. Over here there are not that many to choose from that fits my preference in appearance so I am inclined to try and make this work without getting myself into too much trouble and appreciate any advice or thoughts you may have.

I did push it up to around 160mph and it still felt super smooth and without vibrations.

Thanks.

jakematic

I've barely been able to get anything further than a test drive around the block with used vehicles.

Am going to your dealer from now on

mishar

Rotors, calipers and transmission can't be damaged by lowering car to the ground without wheels. I would check body. Ask them to hoist it up an check. Also ask for TPMS sensors and brake job. They are not selling used Corolla.