I bought my 1987 S4 as a non runner but now it is and I find the steering extremely heavy at parking speeds. I have not driven another for comparison but I have some new observations.

1) Just recently we had a cold snap (35F) and when I first started, the steering almost felt reasonable. As soon as the fluid warmed it was back to the usual 2 handed grunt to park it.

2) With the wheels off the ground it is extremely easy to move the wheels from lock to lock with the engine stopped.

Could there be an internal leak in the rack which then allows equal pressure to both sides resulting in zero boost?
Did the low temperature tighten up a seal for a few blissful moments?

Any thoughts??

did you replace the Hi pressure line from the back of the pump to the rack?? Hi pressure line is the one that's flexible and runs along the top or the shock tower and it has a round piece of rubber on it this is a restriction for the LO speed boost, if you replaced the line then you have less boost at idle.
Anyhow I would suggest that you change the fluid, and see if the old stuff has any silver particles in it.
If it does then the pumps probably going bad..
To change fluid, undo one of the lines to the bottom of the rack and then turn the wheels back and forth with the engine off this will get most of the fluid out.
Did you mix up the lines? Return line is to the rear IIRC.

Is the steering wheel maybe rubbing against the pod?
Drive belt slipping over the pulley?

I 've seen damaged steering bearings (in the steering axle to the steering wheel) cause unreasonably heavy steering. Ask Graham T.



My 89 S4 has suddenly developed a power steering fault with following  symptoms: Perfect when starting from cold but after aprox. 5 miles  looses assistance in straight ahead position (i.e. becomes heavy for  minor movements) but is still OK for medium to full turns. No noises,  fluid topped up and system bled and belt adjusted but symptoms remain.

Before starting to replace parts (I have a donor car) can anyone tell me if this is pump or rack? I replaced the rack boots about 2 months ago and there were no fluid leaks then.

Thanks in advance,
Mike Dunnion
Dublin, Ireland

it could also be a steering bearing that is bad, not related to the hydraulic system. This causes rather heavy minor movement and tram-railing effects.

maybe I was not very clear.
The meant top bearing at the steering axle from wheel to the rack, just below the steering wheel, sometimes becomes broken or turns heavy. Misalignment could be a cause, pressure on the bearing in axial way. (hope I said that right) What happens is that you can steer into turns without problems but have a hard time correcting small deviations from the center of the road. It keeps drifting off.
hope that helps.

Maybe it is something in the rack. I've seen the rack having vertical play at the steering rods. When you turn the wheel the rods tend to move not only in and out, but also up and down, causing some unwanted sloppy responsiveness.

This sounds very like a problem I had. It was rust in the roller bearing at the top of the rack. This is not a bearing for the rotation of the
steering column but between the part connected to the wheel and the part connected to the pinion, i.e. movement between these two operates the valves which direct the fluid to the rack. When it gets stiff,  assistance is intermittent.

If you dribble some thin oil around where the steering column enters the rack, then waggle the steering wheel with the tyres on the ground, you may be able to free it up.