I have a partial loss of power steering when the engine gets warm. When cold it's normal, then after a few minutes as soon as I see the coolant temp gauge begin to rise above zero, the power steering starts to get heavier. It never goes completely, it's always driveable but it's definitely low on power, I'd say around 50%.

The fluid level was slightly low so I topped it up - made no difference.

Any ideas what could be wrong?

Correction: title should ready "...when warm"

 

When do you notice that the steering gets heavier? While parking? While driving down the highway?

 

I notice it any time I have to steer - going around corners etc.

Also, I can actually tell even when I'm going in a relatively straight line because I can kind of feel the road a bit more through the wheel.

 

weird. any noises or any other symptoms?

maybe a worn out belt slipping when it gets warm?

 

Hhhmmmm. The A6 that you have has a solenoid on the steering rack that makes the steering heavier above a certain speed. I find it hardly noticable. There is a relay under the steering column that you could try pulling to see if that changes anything. It is clearly labelled. In fact some people pull the relay to get a heavier steering at all times. If you pull the relay and the steering stays consistently heaver, then the solenoid could be the issue. Otheriwse, it's either the pump or the rack. Since the pump isn't making noise, ... Replacing the rack is a LOVELY job!!!

To pull the relay, pull straight back on the trim piece just above the steering column. Remove the fuse cover on the side of the dash, then remove 5 screws that hold the lower trim piece in place and rotate it out to remove. The relay will be staring at you.

Good luck,

Bob

 

Thanks for the advice. I haven't had a chance to look for the solenoid yet.

But I did notice that the steering seems normal at very low speeds, like, when parking etc. or if I slow almost to a stop before cornering.

I hadn't noticed it until you mentioned about the solenoid, but I can definitely notice a difference now.

The heaviness seems to come somewhere between 5 and 10 mph but it's hard to pinpoint. I'm still sure that it's not there at all when cold however.

 

I'm curious, is this variation in the level of power assist gradual, or is it just 2 distinct settings?

Today I could have sworn I could feel 3 distinct levels of power. When I drove out of my garage, it felt more or less normal, then it seemed to get a little heavier as I drove away, then when the engine warmed up after a couple of miles, it got much heavier. Would such wide variation rule out the relay or solenoid being the issue? Haven't had a chance to try removing it yet.