codewhore

So it's been cold lately for a few days, like -35 Celcius cold. Drove the car without issue Friday despite the groan-like whine of what I would typically think of as cold belts or power steering on any other car that I've owned. I also believed this to be the case of the S4 based on things I've read here.

Started the car once on Saturday to just warm it up a bit and make sure that it didn't freeze too solid. I notice a pulsing groan coming from the engine, different from the constant tone described above. This one is a bit louder and is rythmic, groans for about 1 second, 2-3 second pause, and so on. Moving the steering wheels causes more noise too. But again nothing that struck me as really bad.

Monday morning is when I actually drove the car next. Start it up, drive to the corner store near work and turn off the car when I go in. When I start up the car a few minutes later the power steering is cutting in and out.

Get to work, park the car until noon. Fluid level is right at Max but yet there is fluid on the engine cover that surrounds the reservoir, all over the reservoir itself and down in the engine. WTF?

Start the car up and no power steering at all. The car has been parked since then. I STFA and see a comment about a TSB on needing to fill the reservoir up past the max mark. So I do that and start the car up, I have some power steering but it's cutting in and out still. While the car is running I go and open the reservoir and it is empty. So I grab the bottle and pour some more in and all of a sudden there is brown fluid/foam churning around in the reservoir. I put the lid on and shut off the car. Now there is brown fluid/foam oozing out of the tiny whole in the cap of the reservoir...at least I know where the fluid espaced in the first place.

For those that had their steering pump die on them does this sound similar to your experience? What is the brown fluid/foam all about since the new fluid is green.

Any words of wisdom would be greatly appreciated.

DrGP

I believe you need a new PS pump. I think yours is fried. Not an uncommon thing with the S4. Easy fix

codewhore

New pump is what I suspect I'll be buying next

daveak05

My guess would be that you have a malfunctioning PS pump, which is creating a bunch of air in there AND overheating the fluid, hence the forced overflow.

Per the TSB, it should be filled to max cold, not above max.

Brown fluid? I know it can get discolored over time, but the correct fluid is green, as you mentioned. It's probably overheating to near boiling point, discoloring the fluid and causing the foaming.

daveak05

fill to max line cold, and when checking warm, it can be as high as 10mm above max. I would NOT fill above max.

codewhore

i think you nailed it. i talked to an Audi tech about the issue and he said basically the same thing

DrGP

I, at one time had a copy of it in my possession. It recommended filling 10 mms above the max. The S4s have had a mysterious problem of disappearing fluid. To date I don't believe that Audi has fixed the problem. Filling it 10mms ABOVE the max pretty much insured that it would not fall below max between service intervals, at which time the techs could check and refill the reservoir. Adding PS fluid was cheaper than actually fixing the problem.

daveak05

replaces that procedure.

Old procedure:

PS fluid cold(68 degrees or less)
Fill to min
PS Fluid warm(op temp)
will rise to between min and max

TSB procedure:
PS Fluid Cold(68 degress or less)
Fill to max

PS Fluid warm(op temp)
can rise 10mm above max

Mine was at min cold, just as it would have been filled at the factory under the old method. I filled to max cold. I just did this, my car has low miles(16k). Note that getting it from min to max was probably a couple ounces, no more.

There is no mention anywhere I have seen about filling 10mm above max, cold. However, if a tech is doing it with engine warm, then yeh, makes sense...same difference

My Bentley is early 06 release version, and I believe that TSB was dated in 05, but would have to look again to verify that.

hugj

Dead pump- just had mine replaced last week but this one is dying now as well- back to dealer