The initial good news seems to be that the replacement solenoid valve block seems to have resolved the G291 fault code. Before it came up pretty much every time I drove the car. Drove it a few times today and nothing, fingers crossed.
Following doing the front discs and pads I wanted to also do a brake flush. I have a Motive Power pressure bleeder, best brake investment made. Makes one person brake bleeding simple and way faster.
I put 2 quarts through the system, and this came out of the rear brakes
http://audirevolution.net/addons/albums/images/467854342.jpg
The bleed nipples we almost seized tight on the rear, I get the distinct feeling its been a while since the rears were flushed.
Fronts were better, but happy to know they full system is done now.
man, the fluid was DONE. (sigh) I guess I need to do mine…Just so tedious without a pressure bleeder and an extra person. I’ve been dragging my feet on doing my brakes period - my front rotors are done. I want the JHM LW rotors, but after ponying up $2k for a new intake my spousal approved budget for the year is shot.
Any plans for the car other than fixing the list of gremlins?
Not really any plans to modify it, other than a little more noise. So thinking about possibly removing the rear resonators, or opening up the rear muffler to see if you can gut the a little for noise.
Working on an annoying noise in the car since buying it, sounds like a pebble rolling inside the passenger rear door when you really get on and off the gas. After removing both front and rear door cards, nothing there.
Tracked it down to the door sill chassis rail. It looks like the sill trim was removed previously and the clips that fix the trim snapped off and now rolling up and down the chassis. You cannot see inside or get access to remove it. I dropped some clear silicon down the clip hole, drove the car and caught part of the clip. Leaving the silicon to harden and hopefully trap the roaming clip. Fingers crossed that will stop the rattling, as it is bloody annoying.
So some good news on the car, ran a VCDS and the G291 suspension code is gone for good. I think its the first time since owning the car that I haven’t had some sort of suspension code.
Also the silicon in the frame rail seems to have addressed the annoying rattling trim.
Still have a few outstanding items:
- VCDS codes for the Alarm horn (Which is odd as it works when I set the alarm off)
- Code for the rear right footwell heater, seems a common issue. Not something that really bothers me day to day.
- TPMS sensors out, again another one that doesn’t bother me as I switched the warning off. Will replace them when I get new tires.
- Trunk opens on the 2nd try, first try lifts the RHS first then stops, 2nd try opens it. Anyone had any luck adjusting the hinges to fix this?
- Seeing what I would call excessive condensations in the headlights usually after a car wash, it drys but its annoying. Will have to look into this more.
- Still have some maintenance that I want to address - new fuel pump, wipers, tranny/diff oil changes.
Other than the maintenance I could ignore all of the above, but enjoy working on the car so unless a big $$ fix will probably address sooner or later. When they are running well they are great cars 
Is it hard to DIY for the headlights?
It’s very easy just takes time. Hardest part is taking the bumper cover off if you want to remove the headlights. You could do it with them fitted but it’s a little messy.
The actual sanding just takes time to go from 800 to 5000, probably 30 minutes a light. Polishing with an orbital is simple, then sealing is simple just wait an hr between coats.
Very satisfying once it’s done and your lights look like new
Headlights look great. Nice to see the car is comming along.
I did the toothpaste trick with my headlights and it wasnt quite as sharp as yours but you are right it does make you feel much better and it is something most people can do on there own.
A brief update, I haven’t had much of a chance to drive the car lately. But have put on 2,000 miles since the last round of work I did on it.
I get it on the lift and had a look around it and please to say no more oil leaks which was one of my concerns that it was leaking from ore areas than just the oil filter housing. Been close to 3,000 since that repair.
Also ran a diagnostic and no suspension G291 codes, looks like the valve block finally fixed that one.
Car is running great, averages 16mpg which I don’t think is so bad for such a monster engine.
Looking forward to the weather warming up here in MN so that I can look into a few minor issues, be interested if anyone has any feedback on these:
- Front suspension creaks a bit when the weather is really cold below 0F, seems to be a common fault with A8’s. Many post that is the suspension arms to the hood seal. So I will be looking onto that.
- Front LH headlight has bad condensation after I wash the car, RH has it a bit but not that bad. I need to pull the bumper to investigate further but it does seem to be a common A8 issue.
- Whilst I am into the lights I want to look at getting some better main beam bulbs as for a 10yr old car they are not great. As it looks like its easier to change them with the lights out of the car as there isn’t much room with them in situ.
- Again whilst the bumper is off I’ll replace the suspension compressor sealing ring and look at the mounting rubbers as I can feel the vibration from mine when it runs occasionally.
Be interested in anyone has any experience and fixes for the headlight issues, be nice to have brighter/dryer headlights
Update: Just rolled over the 100k mark last week, glad to say it was completely uneventful!
Did some work on the car this weekend to address a few of my minor gripes, sorry to say that I didn’t take any pics of the work.
When I purchased the car I noticed that the LHS front inner fender trim did not fit inside the fender lip, so water would get through the gap in the area to the compressor, I thought it was just bad fitment, but with age and maybe some botched repairs I couldn’t get it to fit correctly so purchased a new one $120 from ECS. I expect this gap/fitment issue didn’t help with my headlight fogging as clearly water could be splashed behind the light area. Especially when I put the car through touchless car washes here in MN every few days to wash off the salt. I also cut a section out of the old LH one to repair a hole in the RH, looked like the car was driven without the liners being properly fitted and they had some tire rub that wore through the liner.
Headlights - whilst I love driving the car the performance of the headlights at night left a lot to be desired. The output was weak in both low and high beams. I had read that older xenon bulbs degrade, so decided to replace them. Whilst there I also wanted to try and fix the condensation issue that I have. I don’t think that there is any way you can get to the bulbs from inside the hood, and I would suggest its still pretty tough getting to them from the wheel fender liners. As I wanted to give them a good check over, I went the whole hog and removed them. To be honest it’s not that difficult to remove the front bumper and it made it way easier to work on the lights on my bench.
Be very careful taking the back off the lights, with the heat and age the plastic cover locking tabs get very brittle and can easily be broken. With the back off I ran a hairdryer through the lights for a few minutes to completely dry they out. Replaced the bulbs with Osram 66240NB Xenarc D2S Nightbreakers, $99 off Amazon. I couldn’t see any damage to the light cases that would allow water in, but the overall design and aging plastics cannot be completely water/vapor tight. I cleaned the seals of the bulb covers and added copious amount of petroleum jelly in an attempt to help them seal.
With the bumper off I decided to refurb the compressor, I don’t have any codes off it pointing to issues, however I don’t know how old it is and I do notice when it was running I feel vibrations through the car. Removing it is easy with the bumper off, I noticed that during the previous repair (by Audi) that 2 of the bolts securing the compressor were stripped. With the compressor out I replaced the piston sealing ring, they run around $30 off Ebay. Mine showed some signs of wear but it wasn’t terrible. I also replaced the compressor isolation rubbers and mounts $93 from ECS. The compressor was mounted with what looked like a mix of bolts/washers and rubbers, again a supposed Audi repair. The new mounts let the compressor float more than the previous installation. Refitting it, replacing the stripped bolts and ensuring cables and lines didn’t touch the compressor to isolate the vibrations.
Whilst under the car I also greased the sway bar to chassis mounts, some suggest that with age these cause the squeak/groan in the suspension that I seem to get when it’s really cold. Time and weather will tell if that is the fix.
Put the car back together and ran it a few miles last night. First surprise the that the Osram bulbs are a massive improvement, obviously I can’t compare new Audi bulbs to them so maybe replacing the bulbs with Audi parts would also have an improvement. I was really happily surprised, they illuminate the road now as well and my wife’s 2017 Grand Cherokee. Where before they were defiantly a weak area, to the point where I was thinking I might sell the car and get something else. Living in MN with the long winters means you need good lights, and with these new bulbs I’m glad to say I now have them. I’d suggest swapping them out ever 4-5yrs, as the brightness seems to diminished with age, other than the PITA to change them it’s a cheap improvement I’d recommend everyone does.
Also pleased with the compressor rebuild, as I haven’t noticed it running now, so the new mounts seems to have addressed the vibration.
Finally took the car through a car wash and I don’t seem to have any condensation in the lights, I think a mix of replacing/repairing the fender liners to seal properly, and having a better seal on the bulb covers may have addressed the issue. I noticed last night when I did the final adjustment of the lights (after the car wash) that the 2 adjusters had some water pooled on top. These are known to leak through the O’rings, I couldn’t see how to remove these to replace the O’rings and didn’t want to risk breaking them. I’ll leave them to completely dry out and will smear some silicon to seal them as a belt and braces measure.
Not sure what’s next on the list!, the trunk twist that means I need to hit the opening button twice to get it to open is my next job.
Just read this update. Looks like you’ve had your hands full.
Where in MN are you? I head down from Winnipeg to Minneapolis for Cars & Coffee a few times a year. Know quite a few of the Eurowerks guys.
I live west of the cities, didn’t manage to get to cars and coffee last year too busy with kids stuff. Will defiantly be going this year however.
Quick update on the car, it’s been really cold here last few days and no squeaking suspension, so the lubing of the sway bar mounts seems to have don’t the trick.
Also headlights are still condensation free following 2 car washes. Really pleased with this as that was probably one of the biggest annoyances to come out to the car and see sub-tropical headlights.
Love following along. Its great to see you continue to make the forward progress with the car.
Thanks for all the updates, keep em coming…as long as nothing actually breaks!
Thanks for the comments.
Recently I have noticed that every now and then I could smell gas in the garage after parking the car, no sign of leaks but definitely a smell of gas, and that I could also smell it sometimes when I drove the car with the sunroof in tilt. Definitely didn’t have that issue when I purchased the car.
Tracked it down to when the car has just been filled with gas, when it was 3/4 full I didn’t notice it so much. Put the car on the lift, no signs of leaks or smell of gas under the car. Rear RH wheel off and fender liner off, again no leaks from the filler neck or smell. Opened the gas tank inspection plates in the trunk and there the smell was, no sign of leaks but it would seem the seals were allowing a slight weep hence the fumes. So I replaced the seals, there are 2, for the right and right tanks. Seals are pretty cheap both were $36 from Audi, you also need a special tool to release the locking ring, its $40 on Amazon just search T10202.
As mentioned they are easy to get to, just remove the trunk carpet and you will see the plates to remove
http://audirevolution.net/addons/albums/images/320671232.jpg
Before you release the locking ring, clean the area as it’s pretty dusty and you dont want it getting into the tank, I blew the area off with an airline. Then remove the electrical connections and the fuel lines.
The tool you need to remove the locking ring.
http://audirevolution.net/addons/albums/images/410090261.jpg
My old seals were damp with fuel, new seal in place
http://audirevolution.net/addons/albums/images/877587584.jpg
Real simple fix, and it seems to have completely resolved the fuel smell issue.
Another great tip. Thanks for posting this.
Been a while since I posted last, mix of messing around with a summer car and glad to say the S8 running great. I’ve ran it for 8,500 miles since purchasing it and only recently had to top the oil up, I’m guessing its running around 3/4 of a quart every 7-8,000 miles. All I am glad to say through combustion vs leaking. The car is around 6,000 with no leaking which I’m really happy with.
A few months ago I started getting a intermittent CEL for S1 B1 O2 sensor, I tried cleaning up all the O2 sensor contacts but it made no difference. O2 sensors generally send the fear of god into S8 owners as 2 out of the 8 sensors on the car are an engine out to replace. Honestly I dreaded it, however luckily the B1 S1 is the easiest to replace, its the Bank 1 upstream sensor, as below.
http://audirevolution.net/addons/albums/images/484315461.jpeg
A quick search seemed to show that the Audi sensor was $200+, its a Bosch sensor and the exact same sensor and connector is Bosch 17363 available for $83 on Amazon, Sensor was a really simple repair. Only downside is the original Audi sensor had a lead around 12 inches long, the Amazon sensor has a lead around 36 inches long, other than that its exactly the same. You could cut and splice it, I decided just to loop the lead and cable tie it up.
http://audirevolution.net/addons/albums/images/226840224.jpeg
Cleared the codes, drove it for 10 miles and all seems well, no more CELs and its running great, however I will say that when I did have the CEL the car ran as good as ever with no noticeable MPG or power drop
With a few days of vacation decided to Leatherique the seats, when I purchased the car last year I had it detailed and they supposedly cleaned the leather, but it never really looked great.
Leatherique does a great job, but it a bit time consuming and messy. Unfortunately due to the time it takes I haven’t gotten an exact before and after.but here is a before of the drivers seat.
http://audirevolution.net/addons/albums/images/753433705.jpg
First you massage in the oil to the seats, here is a pic of the oil applied. I just rub it in by hand. You them leave the cars 24hrs in the sun for the oil to soak into the leather, after a few hrs the oil had totally been absorbed to I applied more.
Next day you clean the oil off with the cleaner, its not that easy to see the difference after cleaning 1/2, but here goes
http://audirevolution.net/addons/albums/images/650380262.jpg
And here is the final cleaned seat
http://audirevolution.net/addons/albums/images/322351711.jpg
Overall I can see the difference, the seats, dash and steering wheel have the dull finish of clean leather, the seats still show wear but they look and feel great. Worth the time and effort to keep the S8 looking great.
Pleased to say that all of the mechanics on the car are working pretty much as intended. Next on the list is to address some of the cosmetics, mainly around the front bumper. It was always rough from when I purchased it, it looked fine from 5ft but close up and it has many stone chips and showed a poor past repair. Recently I also clipped a post on the front right when parking, all my own fault I’m embarrassed to say. Leaving the car with a damaged from lip, cracked side marker and side trim.
As you can see it’s dinged up.
http://audirevolution.net/addons/albums/images/52987765.jpg
As I have mentioned before the car is my DD (now my winter DD and long trip car) and life here in MN is tough on cars in the winter, so making the car perfect cosmetically isn’t really worth it for me. With this in mind paying $$$ for a professional repaint and repair wasn’t in my plan. Some might say foolishly I decided to undertake the repair myself. HOWEVER first and foremost I will say in advance that unlike mechanical repairs which to me is easily learnt and logical, bodywork is a skill/black art and as you will see over the next few threads its clearly not a skill that I possess. I know the basics but that’s about it, happy for other with better experience and skills to weigh in on what I’m doing wrong.
First of all I stripped the bumper off, that’s a pretty simple 30 minute job. Stripping the trim off the bumper is also easy with torx screws holding the grill in place. At first I was just going to paint the bumper, and that would have been the easy part relatively speaking. However my grill was looking rough after 100k miles, so I decided to go all in and paint the grey grill black as well. Removing the chrome off the grill edge is easy and held in place by torx screws. I didn’t want to just paint over the chrome trim so decided to remove all of them and the Audi logo. They are held in by clips which after 11 years are a bit on the brittle side, I took my time and ended up only breaking a few of the tabs. I think I will probably epoxy all of these back in when I put it together to be safe. Grill stripped and ready for prep and paint.
http://audirevolution.net/addons/albums/images/440807029.jpg
Next was the structural repair of the bumper, as you can see mine was broken and a previous repair before my ownership basically entailed zip tying the parts together. This repair worked but I didn’t like it, as you can see below.
http://audirevolution.net/addons/albums/images/212723124.jpg
You can repair most bumpers by plastic welding breaks in the material, it’s not the most attractive repair but works using a soldering iron to melt and fuse the material together, you can also use zip ties as welding rod/filler to strengthen the repair. After welding the parts together, I then reinforced the weld with epoxy resin. You cant see this on the car so cosmetics are not that important but it has a little more structural integrity than a zip tie.
http://audirevolution.net/addons/albums/images/855566501.jpg
I’m at the laborious stage of sanding out the chips, imperfections and previous repairs, it takes time but my little understanding of bodywork is that the prep is everything.
http://audirevolution.net/addons/albums/images/111235273.jpg
Filled the post ding, go lightly on building up the bondo vs lathering on a ton of it that then takes you hours to sand down, I also learned very quickly to us a little less hardener than recommended as it was going off in minutes, not giving you much time to work with it.
Clearly more filling and sanding to come before I even think about the first spray of paint.
Nice thread. I have the same car with all black seats. Will try the Leatherique tomorrow