Moonlightblue

I have a 12 month old 2016 with 12k miles on it. When I got into my car after work today to drive home, as I do each day, there was a problem with my power steering. I can't say it failed entirely, as I was still able to drive the car, and the issue seemed to mostly (about 80%) resolve after I drove it for about 30 minutes. I had difficulty turning the wheel, there was much resistance turning it, but not as if the power steering entirely failed, but as if it had mostly failed. It was 17 degrees out, but my car has sat for longer in colder temperatures in the past without such issue. After driving it home (45m drive) It seems to have mostly corrected itself, but the alignment now seems off. I'll be taking it in to the dealer service dept tomorrow morning to have it looked at. Anyone experience anything remotely similar in a 2016?? I think I read of a similar issue in the C7, but not the C7.5. I'm not even sure where the power steering reservoir is so I can check the fluid level. Should I have had the power steering fluid flushed or topped off by now?

newmoon

Just want to point out that there is no power steering fluid. It's electric power steering so the assist is provided through an electric motor sitting directly on the steering rack. There could be a fault in this system causing your problems.

Moonlightblue

Thanks, will be sure to check this out..

Moonlightblue

Got my car out of my (somewhat) heated garage this morning, and the problem was gone. Took it into the dealer's service dept, and you guessed it, they said it was fine. The tech who checked it out told me that I had too much air in my tires, and that was probably it. Oh, and he said I had my steering on dynamic in the "individual" setting, and that I was probably just experiencing that effect. He checked the front suspension components, the steering, and took it for a test drive and said it all checked out. No faults thrown, no error lights on the matrix. And it couldn't be the electronic motor on top of the steering rack, because he's never seen those go (this guy looked to be in his mid-20s, so I'm not sure exactly how long it's been that he's never seen these go).
So I took it to work today, got out at 5pm, started her up (18 degrees out today), and wouldn't you know it? Same problem. It was very hard to turn the wheel, and it remained like that for about 30 minutes of driving.
So it has something to do with sitting in the cold. Anyone experience anything remotely similar?
I should say, my wife's Q5 sits out in the cold every night, and nothing remotely similar happens to her steering.

DanfZX14

Never happened with my 2015 and it's been freaking cold here.

Nakedhoof

A motor not working would likely throw a code, even if it didn't have a warning light to notify you. The record of the fault would be in the ECU memory for the power steering module. If he didn't actually read the fault code list, he wouldn't see it. I see that you say there were no faults found, but it sounds like something that would definitely show up.

Moonlightblue

But it didn't seem as if the motor had stopped working, because I was still able to drive it with only moderate difficulty. I've driven a vehicle where the power steering totally went out, and this wasn't that. It just seemed as if the motor may have slowed. Would it have thrown a fault if the motor had slowed down, possibly due to the low air temperature, but not stopped entirely?

radarguy

That diagnosis says it all. If anything, higher tire pressure would make the steering easier. Codes or not, based on your observations something is wrong and the dealer technician has no clue. I would discuss it with the service manager or find another dealer. If it should totally fail while you are going around a curve you could be in serious trouble.

newmoon

Maybe you should check your tire pressures. From this thread: https://www.audiworld.com/forums/a6-...tires-2910757/ you can see that you lose 1 psi for every 10F drop. So it's possible that they could drop way down to ~25 psi if it's really cold, and this will definitely make your steering feel very heavy, or your alignment seem off if it's on one side.

Also, driving the car heats up the tires so they could pick up 3-5 psi on the way to the dealer or on your drive home, plus some more if the dealer's garage is heated, making the problem seem to go away. The tire pressures should be set when it's cold and the car is undriven.