jbase

Hello all.

I am an Audi A5 user since 2010, I bought the car used when it was around 2 years old.

Right when I got to drive it, I heard some kind of constant whine -- not too loud -- but sounded like a poor stereo install, if you know what I mean.

This was frustrating so I started seeing dealers and techs and they all diagnosed it as noise coming from the power steering system. If you put an ear next to the steering wheel, you can hear it and also vibration on the wheel itself.

Obviously, as it was an almost new car, it wasn't steering pump whine, and the sound was different. Also, the sound got quiter when rotating the wheel, whilst if it were a faulty pump, on the contrary, it would only get louder.

As the dealer tech suggested I replaced (in this order):

- power steering fluid
- power steering pump (still)
- power steering high-pressure hose

Spent around $800 already. No result. Pissed. System still whining. Thing is, some A5's have this problem, some just don't. Dealer says it's not a problem since system is not leaking and working as it should.

There are only 2 things left to replace:

- servotronic valve ($250)
- steering rack ($1100)

So... Just to not waste any more money, maybe someone already solved this problem and knows what it is?

Thanks!!

jbase

Hi, I had steering rack replaced today. The whine is not gone.

vecinu

Wow, that's really unfortunate.

It's a shame the dealer couldn't pinpoint the exact source of the noise.

Are you going to do the servotronic valve job as well to see if that fixes it?

jbase

I installed a steering rack w/o servotronic valve to eliminate another problem.

I think I found another cause of whine, it's the reservoir. If you put you ear next to the driver's side front wing, you can hear the whine clearly. The reservoir vibrates like crazy and causes whine to be heard in passenger compartment. If we somehow isolate the reservoir from car body, the whine will be much quiter. In fact I unscrewed the reservoir: while it's not touching anything, the whine is almost gone.

Some article I read about RS5 gave me ideas: the owner had the same problem and consulted the dealer, and the tech guy moved some hose that was touching the wing and the whine was gone. I can't seem to find this article now, think it was on this forum...

s4master1

there's a filter built in the reservoir and gets very noisy when clogging up
easy way to find out is sticking a screwdriver thru the filter, the noise disappears almost immediately.
any previous work done on hoses/rack?
sometimes people use wrong size banjo bolts with smaller or bigger holes and create difference in pressure.

jbase

I heard the thing about filter clogging so many times. ))))

This only happens on A6s, never happends on A5s, the reservoir/filter system is different.

Actually, replacing the reservoir (with the filter altogether) was the first thing I did. Has nothing to do with the noise/whine.