Gtopb

Good morning everyone,
I am new member to the forum and I joined to seek for any advices that causes a noticeable vibration/shake while reversing on a slight hill.
I own a 2017 Audi A4 B9 Quattro S line. Engine code is CYR, 2.0TFSI; Making 185kw or 252hp to a 7 speed dct. Prior to this ownership, I had a Audi A5 coupe B8 quattro with 2.0tfsi at 155kw.
I can't really call myself a car guy since both cars were bone stock but I wish to get some advices to what's happening in the car.
In my opinion, I feel like the 7 speed dct in the b8 was more reactive and mechanical? Than the one that is fitted now in my b9 A4.

Recently, my b9 A4 started acting a little strange especially when I reverse on a very slight hill, or when I a go forward in a bit more steeper hill. No more than an average driveway angle. I feel like there is some vibration or shaking in the transmission while the car is just starting to move; possibly in the process of the clutch getting fully engaged to the engine. This shake goes away after it gains a bit of speed, maybe 10kmh.
I dont know what is causing, I really am hoping that it isn't a worn out clutch cuz its got 30000km on it, and been launched 6 or less time in the past 4 years. The reason is, 2 years ago, when I tried launching it for the last time, I had auto hold on, and in this process, car didn't launch and I could smell the clutch burn.

Would getting a transmission mount maybe fix this? Or should I go to the dealership and get it examined? My b8 a5 never had this issue. What are your thoughts ?

Teemos

I'd go to the dealer from what I understand the DSG are rated to do 200 launches then the computer will deny you. You should still have smooth engagement though maybe Auto hold did mess it up not sure. It's the first time I heard of this.

BeezySBaby

A couple of things that might put your mind at ease -- launching your car should almost certainly have no effect on your transmission behavior, especially when considering you've not modified it to outside of manufacturer power specifications. Second, if the car just 'did not launch', what you were most likely smelling is burning rear brake pads trying to hold the car back as you added gas without the brakes being fully depressed. My car recently developed what seems to check out as "quattro rumble" in the last 5000 miles or so, and I can describe that as a slightly bigger rumble than normal with the wheels locked turning one way or another -- is that your case here, or are the wheels completely straight? I'd venture to guess this is just your quattro system breaking in a little bit, and causing some jutter, but maybe after answering some of these questions we'll have a better idea!

Gtopb

Yes you are correct. I also heard that the launches are limited, although I do not know exactly what the limit is. Assuming the limit is 200 as you replied, I guess I still have at least 190 left. I only launched the car like 6 times for the past 4 years.
In regards to visiting a mechanic or dealership, I live in Sydney Australia and due to recent Covid restriction, we aren't allowed to leave no more than 5km from home lol. But I'll defo visit a mechanic when the restriction is eased. Thanks mate

Gtopb

In regards to launching and it's impact on clutch, my previous car A5, had a launching rpm of 4000rpm. From what I understand, the launch on the A5 did not 'feel' like the brakes were holding the wheels to build up boost, but rather closer to being a manual launch; clutch drop. I know cars can be programmed differently depending on the region. I know that it isnt common for b8.5s to launch at 42000 rpm, but mine did here in Australia. The launch in the A5 felt way way way more aggresive than the current b9 a4. The current b9 A4 is like what you said, brake holding the wheel so that the turbo builds boost; which is audibly noticeable. But my concern was that whilst the boost is being built, there must be a stronger friction in the clutch from the flywheel being a dct. Dct tranny from my understanding is always engaged, regardless to speed. And because the car felt like it was about to move when i depressed the brake, the autohold did a secondary stopping to the car. I dont really know how to explain haha

regardless, i dont think its the quattro thing cuz diff would'nt cause that big of a significant rattle or shake to the car when only reversing at a slight uphill. Im reversing to go up a hill. But not even steep, just regular drive way or just shopping centre indoor carpark ups and downs.

Gave my mechanic a call and he said he can reprogram the clutch so that, it it stays closer to the flywheel. But he said this is only for cars with worn clutch, which i doubt cuz its just put on 30000km or 18600 miles, and for about a year, car was driven less than 300km a month due to lock down and working from home.

asgardloki

Hi there,
how did you go with this issue? my car seems to have the same issue and need to get it looked it. im also in Sydney.
Cheers!