Drmark

My GTS has a rub - much like the noise / vibration you can get when the power steering fluid is low - when I turn the wheel quickly (typically doing a 3 point turn). I have posted about this before and got no joy, but since then I have met 2 other GTS owners with exactly the same problem. The steering works fine, no leaks and I have put filter part into an ultrasonic bath to clean it (you can't change it) and renewed the fluid. No change. Geometry etc all fine. And one of the other owners had an OPC look at his and they couldn't find anything wrong either.
I have never come across this with other 928's - is it a GTS foible, and if so any ideas why??

sublimate

Perhapes it's cavitation in the pump?

Could you deal with a little less power assist at idle/slow speeds? If so you could try a larger pulley on the PS pump which would cut the speed of the pump and may reduce it.

worf928

No issues with CarChick's GTS. The only steering related noise is due to the PO installing front tires with the wrong aspect ratio.

Jim M.

I also have the same noise on my GTS (93) but it seems to only occur at full lock and when it's cold outside and the car has had a chance to cold soak. I think (WAG) it's the 100 bar power steering pump bypassing fluid because the fluid viscosity is to high when cold. After it warms up it doesn't do it again until cold soaked again.

Jim Mayzurk
93 GTS

Drmark

It does go when it's warm - strange as I thought the rack was identical to the S4 but you're the 4th GTS I have come across. Somewhat reassuring.
Cheers guys.
Mark