Hello. There is a power steering issue on my '05 CTT. The steering feels normal when the vehicle is moving. However, when at a standstill (with brakes on on D, with brakes on or off on P, doesn't matter) and the steering wheel is turned, there is some sort of drag similar to a hydraulic system running out of fluid. The power steering fluid is well topped up. Any ideas on what might be causing this? Thanks for any help.

 

Did you ever find a solution to this problem? My CS started having this problem within the last week.

 

I think they may all do this - sometimes - it's more like a shudder in the wheel movement with a corresponding shudder in the wheel. I did try flushing the PS fluid (Pentosin CHF 202) which may have helped a tiny bit, but the shudder is still there. If you watch your wheels while turning the steering wheel you can see them shudder. I posted about it somewhere (forget which forum) back around the middle of July..

I think it may have something to do with wear on the tires - mine are getting near the end of their useful life (have less then 1/8" left to the wear bars).. but I'm not certain of it. I've been intending to take it past the friendly local dealer sometime soon and have them take a look (Thank Dog it's CPO'd!)..

Just curious - do you have Servotronic? Wondering if that might make a difference..

 

I do not have servotronic. However, the shudder in mine almost feels like my old jeep when it was in 4x4 and you make a slow turn on gravel and the differentials kick in to try and grip.

My 06 CS has about 65% tread life left and it makes the shudder on pavement. So i'm very confident it is not a grip issue. .

I'm taking the CS offroad this weekend to my hunting camp to do some field plot planting, so I will try out the same scenario on some different terrian to see if I can replicate the shudder.

 

I actually have this issue in my 08 GTS. I do have servotronic. It works fine in the morning when I pull out of the garage but by the end of the day, trying to parallel park at 0-1mph is ridiculously tough....acts like no power steering. As you as you get momentum the problem goes away. Pretty frustrating. There's a Porsche Service Bulletin on it but it only says to start the car slower (as in let the car recognize key, then turn on ignition and wait for all the start up tests to finish before engaging into gear) or to replace part of the servotronic system. I did that, but it did nothing. My second thought, was that power was being taken away from my aftermarket stereo, so we disconnected it, and then drove around to see if the problem still occurred....no dice. We are now on the third step which may be to replace how the fluid gets to my steering at 0-1mph....and Porsche is doing some research for me. My thinking is that...since I have power steering in the morning, the fluid is getting where its supposed to go while it sits overnight, but not after use during the day.

 

Just out of curiousity - try rapidly going from lock to lock (engine running) without the truck moving.

I've watched the tires when it does the shudder - and you can them sort of catching, releasing, catching, releasing in sync with the shudder. One thought I had was perhaps the power steering rack is mounted in rubber and the rubber mounts are starting to weaken, allowing it to move when it tries to turn the wheels, then it reaches the limit of it's movement and catches up.

Have to look and see how it's mounted to the chassis.. just looked. It appears to have two bolts holding it to the suspension subframe. The mount points on the steering rack appear to have some sort of rubber bushing the bolts pass through. There is no seperate parts listing for the bushings - only for the entire rack. Hopefully this is the cause of the problem..

 

I know this is an old thread, but wondering if anyone has resolved this issue?
Have noticed the same on my 2005 Turbo, recently. Seems worse on smooth ground like my garage floor, is better out in the driveway or the street which is rougher. I have only 63,000 miles, but have had several other rubber comments on the car go out lately, like the cardan center support, upper engine torque arm, etc. so maybe it is the rubber bushings on the rack going bad or the control arms or upper strut mounts, allowing for play.
I think it might also be the tires. Mine are more worn, I would say 50% worn, and in the summer, with more heat, they are stickier and stiffer since worn, so this chattering happens more? Not to mention these we have wide tires with big footprints, which makes it worse. Also, this is happening on my 20" summer tires, Ill see if it continues on my winter set up on the 18" wheels, which would be less stiff of a tire purely from the lower sidewall height, so maybe it wont happen (I also have almost full tread depth on those).

I have a turbo so I assume I have servotronic.

I can easily see the wheels/tires chattering while parked and turning the wheel. It doesnt happen for the whole travel lock to lock, but somewhat consistently at one location while turning.
The chatter is also much worse when in park and my foot on the brakes. Foot of the brakes when parked still does it, but less.