Dr Awesome's 2007 D3 S8 Ownership Log

I am making this thread to document the ownership of my new (to me) 2007 Audi S8!
I picked it up today and am looking forward to digging in with my new daily driver. My 2001 Stage 3 B5 S4 is now finally going to enjoy retirement as a weekend cruiser.

I am so enthusiastic and excited about this S8 - the driving characteristics are everything my S4 is not: quiet, smooth, comfortable, automatic, and cold (aka working AC :slight_smile:). I am looking forward to enjoying each car for what they were built for. My current goals for the S8 are very simple. I want to refresh and maintain a reliable long distance commuter / road trip machine.

When I went to take a look at it / purchase, I ran a scan with my VCDS. Everything came out clean with no engine related codes. Readiness monitors all passed (aka no indication codes were recently cleared).

First things to address:
It sounds to me like there is a slight exhaust leak under the drivers side, I will have to take a look under the car and see if I can isolate. I suspect a flex pipe? Only noticeable when blipping the throttle around 1800 RPM.

Scan for misfires in VCDS wile WOT to see if there are any misfires which are simply not triggering a CEL. (This is just out of curiosity, the “butt dyno” is not setting off any alarm bells). I test drove a C6 S6 a few years ago that was not sorted at all. The S6 felt like it was asleep compared to the S8.

Bleed the brakes (any recommendation for the preferred brake fluid?) Anything special about bleeding our brakes?

Carbon clean/spacers + Manifold Inspection
Last carbon clean was a decade ago :frowning: I am planning on getting the equipment to walnut blast it myself. While I am in there I would like to inspect the manifold flaps and install JHM Spacers.

After the carbon clean + spacers and having driven it around for a while / uncovered and fixed whatever rears its head, I would like to consider:
JHM ECU / TCU tune
SAI delete
Lightweight crank pulley - would love some feedback if this is a safe bolt on in the sense of retaining the smooth and comfortable luxury ride characteristics. The B5 S4 can have all the NVH in the world, but I am trying to play to the strengths of the S8. I read somewhere on here that one user reported the feel and smoothness of the ride was actually improved after installing the crank pulley. It seems like this is a win win in the HP and Comfort department, which is usually rare.

Final thoughts thinking out loud - I feel like my current goal of a smooth, comfortable, luxury daily driver will experience scope creep. What I mean by that is no doubt in some time I will want to have it all (quiet exhaust and a screaming V10). I know the proper exhaust setup and grail is headers and JHM catback, but I don’t see that in my future. Is it sacrilege to ask if members have used / had success with exhaust cutouts? Seems like an economical way to have it all (albeit no performance gains whatsoever).

Thanks for the read, I am excited to become inundated with the v10 and the D3 S8 platform as a whole!

First off, I got the S6, but as it’s the same engine and quite similar so I offer my opinions.

  1. Brake fluid, just get a decent quality one. As for bleeding, its pretty straight forward, nothing fancy. Just remember to avoid stripping the bleed nut;)

  2. Carbon clean, definitely do this 100%, if u want to save money you can use a strong oven/grill chemical cleaner, soak the intakes, and most gets dissolved, then vaccum is out. Use a low rpm drill or electric screwdriver with a bunch of zip ties jammed into it, basicly works as a brush, and doesnt scratch metal.

  3. Exhaust cutouts, S8 is a bit larger than S6, so you might have more options there, but on the S6 its so extremely tight areas and bends and such, its pretty much only one place for the cutouts, which also has to be custom to avoid losing ground clearange, and thats where the first resonator is, ish. Its tight tho, very close to the drive shaft, but it works. I would recommend vacuum driven valves over electric, because electric might die on you, and requires a completely new set/job/cuts/weld and all that. Vacuum is mechanical, so if the vacuum pump dies, u can simply replace that part alone, 1 min cheap job.

The sound is incredible, i absolute love it, almost straight piped. And the best part is, you can close them for longer cruising, neighbourhoods and police;);), and u can avoid being a cunt. If they were to be open 24/7 u would get a headache, its extremely loud. However, the downside here is that the exhaust is then basicly directly under the cabin, so low rpm high torque you get vibrations into the cabin and drone. (But its worth it).

I’d say looks like a good path.

The JHM LWCP is known to help with a bit more frisky throttle response from the motor and a smoother car over all. The OEM crank pulley is known to have the rubber ring go bad over time and to even have the crank pulley it self fail. So this is a good maintenance part if you ask me.

The JHM ECU/TCU tune are a good way to go for sure. It helps bring the power for the V10 out like you’ve never seen before. It turns the car into a 4 door R8 with S8 comfort and enjoyment.

But as I’m sure you’ve read… maintenance maintenance maintenance… Do the carbon clean. Look into new or cleaned injectors. Change the plugs and coil packs. Inspect the oil separator and PCV system really well. The JHM intake spacers are a big win as well for the cooling of the intake manifold and helping keep carbon at bay for a bit longer. Get all that sorted and you’ll have a smile worthy hotrod that you can enjoy for a LONG time

Thanks for the tips! I am encouraged by your experience with the cutouts kvn!

I will use the chemical method after your advice, as well as justincredible’s posts on the subject.
Paraphrasing Justincredible: use starter fluid to ID your closed valves, 30 min soak with oven cleaner, brush with oven cleaner still in the valve, suck it out, washer fluid + bright light for inspection + repeat as necessary, etc. sounds simple enough and a safe way to clean.

Justincredible: I have a smoke tester, I assume that is the best way to inspect the PCV system? Any advice on the best place to pump the smoke into the system?
Oil separator: just check for cracks?
I saw you also mentioned in another thread that you recommend the oil separator bypass kit from JHM. Should I consider this? I live in Minnesota and sometimes it gets extremely cold.

Planning on replacing the oil filter adapter gasket while I am in there as a precaution and will take stock of everything else I can see.

Thanks again for the feedback! I will update with pictures and progress when I get into it!

Quick update on progress so far:
I have the JHM spacers in my garage, just waiting for the right weekend to pull the IM off and carbon clean + install.

When I purchased the car the previous owner included a spare B&O speaker for the front passenger side, as the front driver side surround was torn and was crackling with bass. I installed the speaker the other weekend and it is sounding much better, although a slight crackle. I can live with it for now, but may replace with an aftermarket speaker I found mentioned on another post. If I go that route I will update with relevant info.

While the door card was off, I dug into my drivers side soft close feature. My car has this feature, but the driver side door was not activating. No motor engagement when the latch was 1/2 depressed, so I thought I had a bad switch. I ordered up a set of switches on Amazon for $6

I got the straight switch type but ended up bending it to get to engage with the lock more consistently. If I were to do it again, I would probably go with this type:

These soft close doors tend to fail due to this switch going bad, or the cable sizing. Unfortunately for me, mine had both issues. The good news is that I have the switch replaced and a used front door latch on the way from ebay that I picked up for $40. I am planning on just harvesting the cable since I know my switch will be good for a while. All in all, not a very difficult project to correct, but a bit of effort to get the features the car came with back online. Fingers crossed the new cable sorts it out the rest of the way.

I installed new headlight bulbs, and used the osram xenarc night breakers: https://a.co/d/864Af8f
I also upgraded the turn assist lights (the side Halogens that turn on when you turn your steering wheel under 40 mph, or use your turn signal while stopped) with these LED ones. Cheap and a huge improvement. No issues / codes / flickering. Highly recommend: https://a.co/d/1H8QdJvhttps://a.co/d/1H8QdJv

Installed a Bluetooth adapter for the MMI system, sounds great and pairs with my phone flawlessly. CD’s are great to let the B&O system shine, but to my ear the Bluetooth sounds absolutely fantastic and puts a smile on my face. https://a.co/d/aCmg7a6

Hardwired a Valentine 1 Gen 2 as well as a VIOFO A119 V3 dashcam - they each installed extremely cleanly and I am really, really happy with how it all sits tucked on either side of the mirror. I tapped into the drivers side dash fuse for the V1 and the passenger side for the VIOFO.

So far have been really loving the S8 and just taking on some of the easier and fun projects getting it back up to par. The previous owner had the fuel injectors cleaned, so for now I am just planning on carbon clean and spacer install, but would entertain an additional cleaning as a future maintenance item down the road.

Some future projects still to come:
Carbon Clean
Spacer Install
Fix an oil leak that is causing oil to drip down the front of the engine (most likely the figure 8 gasket for the oil filter housing)
Upper control arm bushings are cracked, and should be replaced (any recommendations?)
bleed the brakes
balance the wheels (slight vibration noticed 60-75 mph)
replace the TPMS modules (getting a TPMS error akin to a dead TPMS battery)
Window tint? I don’t want the “drug dealer look” but value the privacy + sun protection tinting affords. Is 50% too subtle? I want to keep the lines and elegance of the car. Interested to hear what others think! Thanks for the read

Welcome to the club… Great cars.

The JHM intake spacers are such a great help in so many areas. My self and other S8 guys also went in for the JHM ECU/TCU. It makes the S8 more like an R8. Fun stuff ahead for you it looks like.

Thanks CounttVohn! Your posts have been a huge help thus far!
Somehow as I was writing my post last night I forgot to include the JHM ECU/TCU in my list of future plans! I have heard nothing but great things and can’t wait to go down that route in due time!

So my A8 door latch came in and I am swapping out the cable. It looks like the cable attaches in a different manner to the latch mechanism from the A8 to the S8, so if I were to do it again, I would try to source a specifically S8 door latch w/ soft close cable. They can be found on ebay for around $30 -$40 at the time of my writing. I will give the install a shot nontheless!

As an aside, upon opening my door back up to get at the latch, I was able to inspect the newly replaced driver side 5.25" door speaker. I commented earlier that I still had some crackling when I replaced the speaker with a used one with intact surround. For reasons unknown to me, the crackling has gotten a lot better in the last week, and now I don’t hear it at all, even when the bass comes on. However. When repairing my soft close latch, I inspected the surround on the newly installed (but old and used) speaker, and it has already torn! The rubber on these old surrounds must be getting old! I guess there is a type of glue you can buy for cheap that might help retain the strength of aged surrounds. If you get your hands on an old but intact door speaker, I would suggest using this protectant: https://www.youtube.com/watch?v=jYni5-Oi4ys&ab_channel=SimplySpeakers

In my case, I am going to order some 5.25" foam surrounds and attempt to reinstall and repair the speaker. If that fails, I will find another speaker that matches the specs. It makes me wonder what condition the other door is in, so I may take that on down the road!

Here are the parts I ordered:

This is the third time I have had my door panel off in the past week, and I noticed it is easier to take off (experience + weakening clips). I would suggest if you take your door panel off more than a few times to just buy some new door clips. Mine are intact, but new clips will make a better and more secure connection. Probably overkill but they are pretty cheap and I am going to put new ones in there once I am wrapped up.