A4041.8T

well i've come back to ask for more help. Last time you nice people helped with my coil packs idea and well after all four of those changed no problems but now i have new problem.

When turning the steering wheel it makes a very loud humming noise? only when turn the wheel though going straight no noise. wondering what it could be, i know nothing about steering. any help would be appreciated thank you.

Espritman99

Checked your power steering fluid level? Its on the drivers side near the front headlight and has a green cap. Sounds like your reservoir is empty and the loud whining noise is the PS pump running dry. Avoid driving the car long periods of time with the reservoir empty or you seriously risk wreaking your PS pump and rack. Mine was doing this right when I got the car and wreaked the PS pump bearings. I notice in the cold winter months that it whines when you first start the car and if you start driving the car immediately it will actually blow some of the fluid out the breather in the cap. Best to start your car and let it run a few minutes so that everything gets a chance to warm up a little bit.

A4041.8T

I will check it but last time i looked it was about half full and even though the car is garage and i have my oil pan heater plugged in every night, i always let the car run for at least 5 minutes or more because well leather seats are fricken cold in the winter until the heated seats warm up. thank i will go check it again though.

K04-S4

If the whining noise is coming from the PS Pump, it's likely an air bubble in the center of the centrigual pump causing Cavitation. It needs to be fixed or pump damage can occur.

It takes less than 1 minute to damage an expensive PS Pump by running it with no fluid, Audi suggests no more than 10 seconds operation with no fluid before pump damage occurs.

Our C5 A6 started Cavitating in cold weather. I traced it back to a loose clamp on one of the PS Hoses that was allowing a tiny amount of air to get sucked into the system and collect inside the PS Pump. The fluid level in the reservoir actually went up 1/2" because of added trapped air. Recrimping the clamp stopped the minor fluid seepage (no drips, just seeping) but more importantly it stopped air getting into the system and the Caviation stopped within a few drives.

With engine idling, open reservoir to ensure that fluid level is ~2/3 full and not foamy. If fluid is low and air is displacing fluid inside system, worst case you may actually see the bottom of the reservoir and foaming fluid while hearing cavitation.

A4041.8T

well the noise has been going on for about a week now and steering is fine no differences then before the noise but i've only been driving it 10 km here and there every second day. if the pump goes it should be very hard for me to the turn should it not?

A4041.8T

oh and is there a special type of steering fluid i need for it because i know audi and vw's are bitchy about the type of anti freeze they put in them?

K04-S4

Recommend to use only "Audi Power Steering Fluid".

Your A4 likely shipped new with Audi G2000 PS Fluid that is brown in color. It has been superceeded by Audi G4000 PS Fluid which is deep green in color. The label says G4000 can be mixed with G2000 and nothing else. Personally I prefer not to mix but instead flush out all G2000 to put in all new G4000.

Espritman99

I just buy the cheap power steering fluid you can pick up at any gas station or canadian tire or whatever. Been doing this for the past 1.5 years with no issues whatsoever. I think all that specific pentosin oil or whatever audi uses is just a gimmick. I just fill up every 6-7 months when the pump starts whining and we're off to the races, haha.

A4041.8T

well i went to audi and they gave me some power steering fluid and just like the anti freeze it's made for audi and vw's specifically. Another problem though car won't spray any windshield washer fluid, it has some purple stuff from cdn tire in there rated up to -39 which you know it really doesn't get much colder then that and now it won't spray but with blue in it a day earlier it was fine, line frozen? pump frozen? it makes no noise at all when i pull the lever back but the windshield wipers do move like something should come out.

plankspanker

Had the same issue in cold weather. Headlight washers were frozen shut and causing the fuse to blow because they operate using fluid pressure from the headlight washer pump which is on the same circuit as the windshield washer pump.

Open up your fuse box and check the 25 amp fuse for the washer pump circuit. I carry spare 25 amp fuses because of this. Your headlight washers only operate with headlights on so if the fuse continues to blow when they're on your washer doors are probably frozen shut.