97urS6

Yes, I have a picture of where the cap bolt is on my original rack...

MP4.2+6.0

So, that should be reachable. The adjustment I was referring to is that relatively large nut more inward on the rack from your hand (toward bottom of picture). The clamp area for the tie rod boot is already inside of the steering rack pocketed area beyond the fender opening, but seems like not too far in to reach--in scale that cap bolt is less than an inch inward from the inner boot clamp point, which you can easily see with the tire/wheel off.

Again, if need be you/mechanic can take tie rod out along with its boot to free up a good amount of incremental space in that tight area. Relatively easy to remove. The pain in butt part is getting (fresh) clamp back on the boot, even with a side/angle crimping tool.

97urS6

I'm interested to hear exactly what type of "adjustment" does that nut provide? I'm wondering if it could cure a slight groaning sound that this used rack is making, especially when it's cold.

MP4.2+6.0

The nut eliminates any play you have in the rack--it cinches in the pinion gear tighter to the rack where they meet up. If you have rattle in the steering or feel any play moving wheel back and forth, those would be the indicators of adjustment. Or if too tight, steering will feel like it is binding a bit, and car won't try to return toward center by itself when you let off of steering wheel while driving along.

Failing that, I couldn't say if groan is a wear issue or something else like hydraulics. When I have had steering noise in prior Audis, it has usually been the pump getting tired. For me rack issues have been leaks out the end seals. Fortunately never on my D3.

97urS6

Well I must say that the replacement rack is quite a bit tighter then the original one. So maybe it is worth giving it a try to loosen it up just a tad bit?

97urS6

So as the saga draws to a close... Finally after going back to the shop on 5 different occasions... they finally got the rack relatively close to being centered. For whatever reason they didn't want to do it correctly as per the book (and use the centering bolt that I fabricated for them)... they simply removed the steering wheel and made a best guess at where center is based on full crank right and left and finding half way! UGH.

Anyways, they did another full alignment and for my trouble offered to do another alignment on a different car for gratis. Big whoop!

The real kicker is that both times that I have got the car back from them, I had to reset the Steering Angle Sensor and clear numerous Low Voltage codes, as they let the battery run down too low... even though I tell them every time I bring the car in... to put it on charge. OMG.

So as I mentioned earlier it's relatively close ... well it's actually 10 degrees off actual center! So I think that is as close as this place can get to accurate! Maybe I should feel lucky?

mishar

Actually yes. Those machines require regular calibrating, but that takes time. Doing proper A8 alignment time and brains as it is not every day job. So, some luck needed.

97urS6

Well, that "slight groaning" seems to be getting slightly worse! I took it back to this shop and asked them to adjust the tensioning bolt. They loosened it a bit... probably a quarter turn or so, but really it didn't make any difference with the amount of groaning. Also to note that the groaning only occurs at idle... bump up the rpm's even a little to say 1500 rpms, it goes away! Does that point to the pump? or does it just say that at higher rpms the pump is providing enough pressure to help push the rack around easier?

MP4.2+6.0

Hard to diagnose definitively and across web, but yes that "sounds" like pump to me offhand. In past when I have had weakening pumps on prior Audi's, two other symptoms I have had: 1. stiffer steering/less assistance when cold (like 32F/0C or less) 2. more noise right after start up, particularly when down to freezing but even at 40 or 50F on cold start.

97urS6

Yep, that's sounds like the issue... I'm experiencing all of those issues: more noise when it's cold (less then 10c)... when it warms up, noise almost completely goes away. The steering effort is noticeably stiffer. Dang, looks like I need a new pump! Maybe a refurb is a good option?