2006 Audi S6 C6 V10 build

Hi, I’m gonna make a thread here for anyone interested. I bought a 2006 Audi S6 V10 with 73k miles. In a bit of a rough shape maintenance wise, but I saw some potential in it, and it has reasonable miles.


  • I bought the car 12/2022

  • Scanned VCDS

    • Motor mounts short to ground
    • Cat on bank 3 low efficiency
  • Oil leaks

  • Coolant leaks

  • took the car to the shop 3/2023

  • fixed some oil leaks, still leaks onto the manifold

  • eventually coolant leak came back mysteriously

  • oil leak on manifold became so bad I feared the damn thing will catch fire any minute

  • had it towed to the shop AGAIN 7/2023

  • told them to actually fix it now, cost be damned

Our situation now at 1/2024

  • changed a lot of parts, new motor mounts, head gaskets, spark plug tube gaskets, cam girdle reseal, new alt, starter, steering wheel pump, you name it
  • car still at shop
  • the guys telling me it’s still leaking oil
    • I did some googling myself and brought them some new VVT solenoids, prolly got it now (f*ing hope)
  • can’t get it to run properly, misfiring on cyls 7 and 8
    • new sparks, new coils, I guess I gotta start looking at some new injectors now

Damn. But I’m still hopeful we gonna get it to run eventually.

My plan is to restore the car to 100% stock, tho it has a map for 465hp. Gonna get it as technically sound as possible, maybe install it to “fully loaded” state, and maybe give it MMI3+. Gonna post some pics if you guys want


Here’s the beast pictured from last summer

In the cold snow. Rear lights look like ass, got some replacements for the inner tail lights, just gotta fit em

Congrats. How were the motor mounts to replace? Engine out? Mine are also shot.

Cat efficiency for me is related to an exhaust leak after the cat (broken bolt). Check it if you haven’t already.

Apparently it’s another typical fault for the oil to leak from a gasket near the oil filter housing. Can’t remember exactly, but mine was leaking there and it was a simple fix that was done while carbon cleaning so the intake manifold was off.

1 Like

These cars still look great today. They age really well. great pix.

1 Like

On the 4.2 you can kinda replace them without engine out… Can’t say about the 5.2… The engine was out when they were done.

Gotta see about the exhaust. I’m sure the inspection (katsastus) dude will see it if I can’t

Yeah I changed both oil filter housing O-rings…

If the leak is small enough they won’t necessarily as two of the cats are way up inside the engine and difficult to see from under. Mine passed emissions by just clearing the codes before the inspection. It was only noticed by the exhaust guy who made my cat-back exhaust. When air gets into the exhaust, the post-cat O2 sensor can be fooled into thinking the cat efficiency is lacking.

You can replace motor mounts in car no problem.

1 Like