My power steering was intermittently giving out completely while turning to the right at low speeds, so I did a PS fluid flush using the DIY thread that shows cycling the engine on for a couple seconds at a time and gradually adding more fluid to the reservoir until the fluid being pumped out the other side is clean.

Got all the black junky fluid out, but now my power steering seems to consistently work poorly when I steer to the right, but never when turning to the left. Going right takes more effort on the wheel and I have to push through a "sticky" spot.

Tried the flush, what now? Maybe someone that knows the inner workings of the PS system can tell what the symptoms suggest. There's a little whirring/humming sound still, so
is it possible that I have air in just one side of the system? Is a loose hose letting air in?

Thanks for suggestions, cuz this is irritating me.

 

Sounds like you need a new steering rack. If my memory serves me right, I went through same issue with my 2001 A6 2.7t and had my steering rack replaced to fix the problem. Are you losing power steering fluid too?

 

No, I haven't detected any loss of PS fluid, before or after the flush.

 

Unfortunately, I'd agree with AudiThree - the rack is the only thing that would behave differently at different positions. Any sloppyness in the front end? I've read several posts where people's rack bolts were loose, and maybe when you go to the right there's something binding?
Might try jacking up the front end, taking off the wheels and having a helper move steering back and forth while you check to make sure nothing's loose or binding. Just be real careful 'cause the power steering can crush a body part very easily if you put it in the wrong place...
Jim

 

eejim, I might try that. Front suspension seems very tight and solid, since I just put on new Bilsteins, brakes and a couple control arms, but there's a small chance something didn't get tightened up. I didn't touch the TRE's or anything though.

BTW, what does it take to do a steering rack job yourself if thats what it turns out to be, and what might it cost?

 

i have replaced several for the same problem in my shop. if you have a 2.7t it requires removal of the drivers side down pipe, not fun. but then its pretty simple. couple bolts from the battery area, undo the steering shaft under the dash, tie rods from the knuckles, fluid lines from the bottom after moving some heat shield material, and then drag it out the side through the wheel well. It's a lot of work but not technically difficult. Audi says book time is 10hrs but having done it a numerous times and a shop it usually takes 3-4 hours. So id plan on a weekend if doing yourself. I've never bought a new one but used ones here is Washington are usually about $150 good luck

 

you might look at your Servotronic relay to see which number it is. Back when the cars were new, a common mod was to change the relay to one that had a stiffer/more "sport" feel. Search way back in the archives for more info, pics and part #'s. I did on mine. It basicallly reduces the system pressure under specified conditions. But, as the car got older and the pump and rack more worn, I found the steering effort increased anyway. I put my original relay back in, which gave me some added oomph to the PS again, though it still has decent stiffness. If yours was modded, it may be giving you less effective PS at its current age.

Other replies though are likely right; internally your rack may be blown. I had blown racks on two 85 C3's, but they leaked fluid on the ground. My C5 leaks a tiny bit internally, but I only found it when the tie rod boots were pulled to replace the inner tie rods.

 

I didn't know that was a mod. I might look into it. I just wanted to update. I haven't chalked the problem up to a blown rack quite yet. I replaced the hose clamps I could find on the system and torqued them down pretty good, then exercised the steering real well. After several days of driving, and some cold nights and hot days it seems ALL the air has made its way out of the system (no more noise) plus the PS issue has cleared up a little. Last time I drove it was sooo smooth, both ways - effortless. But it'll take some more time to know if its just temporary, or if I really fixed my issue. Right now my car is in pieces with the driveline dropped to replace the output seal, so I'll test it more when I get it back on the road.

 

sounds to me like the valve inside the rack for turning the one way were stuck. The new fluid may have finally unstuck the valve. If it did happen to be air, i have a good way of removing it. turn the wheel as far hard lock as it can go. shut off the car, but hold it hard there, then start it, turn off, start it, turn off, do it untill the steering works normally.

 

message for "yagovoz"

i just became a member on this forum exactly for this same problem, after reading alot of these posts that get in the depth of relays and servotronic issues, i was expecting to get myself into a big problem, even though i was doubting that an audi part (like the rack) would just go at the 115k i have on my 2001 a6. With this in mind i started with the smallest things to work my way up and the first thing was to put new fluid in it.
im gonna tell you a few things about my problem and you see if you had any of them also.
My steering to the right became way harder to turn than left, that made me feel it would be the rack...

Also, it only did it when the car was moving, not when stopped- that made me think it was the servotronic system because it supposed to activate at different speeds, and mine was only doing it when in movement.

The other thing is that it started doing it when it got really cold outside, december,

A little while passed and the other side started doing it too...

I flushed the fluid completely, used some power steering flush cleaner solution on it also... put the new fluid in and the problem disapeared.

I remembered that a long while ago i had added some PS fluid just cuz i thought it was low but i didnt know that the Audi PS fluid is different than regular auto-zone stuff. I see now that it says on the Genuine Audi PS fluid that u cant mix it with anything else.
Because i did mix it, it had lost its full capabilities and at low temp just wasnt working anymore.
i drove it with the cleaner in the old fluid(before the flush) to get the gunk goin but the problem was still there even with the cleaner added and PS fluid level up to max.

The Audi PS system just doesnt like anything else in there except what it was made for...

Sorry for making this so long but i wished i had read smth like this before going and starting to use the Shut-Gun method on a rack or pump, which can be very expensive but unhelpful. I hope this would help at least a little bit.

Start with the fluid. Its just 30$ at the Audi dealer.