Hello,

I purchased my 2004 2.7T A6 2 years ago. When I first got it I noticed the faint "tick" noise when accelerating. Sounds kind of like a quiet diesel engine. I learned that its common for German cars to tick like that and within a week or so I noticed the sound had gone. Now after 2 years its back. I'm not overly concerned as there has been no change in how the car drives. Just curious on whether I am hearing valve tap or injector tick. The sound is only audible through in the cabin between 2000 and 3500 rpm. You can faintly hear it when idling. You can't hear it outside the car unless the hood is up and its inaudible when driving in my echoing parking garage with the windows down so it’s not very loud. I turned off the radio and told my wife to listen to the noise and she replied "what noise?" It’s just a faint ticking. When I accelerate the ticking increases in frequency but not volume. I had a dealer service/oil change about 250 kms ago and just filled up with gas. After I used about a quarter of my gas the ticking started. So my question is, valve tap or the injectors? I always use top-tier gas but could I have filled up with a bad batch of fuel that causes the injectors to tick? The sound comes from the top of the engine, both sides. Just curious to know what you guys think it may be...

Thanks!

 

I'm not sure but my theory is that...

valve tick should change in frequency with increase in RPMs. Injector tick may change in volume/intensity with increase in RPMs.

someone else feel free to enlighten us both if I am mistaken

 

Should not make any noise. Buy a cheapy mechanic's stethescope and put it on the injectors then the head. The source will be obvious. What kind of oil do you use?

Bob

 

To be honest, not sure. All I know is its oil that meets the Audi standard, dealership does all my maintenance. Last maintenance was 250km ago, in the last week of my warranty (of course).

 

Not sure what brand but the part number for the oil I use is G-052-167-SO....googled it but found nothing.

 

if its the oem oil its castrol something or other. I also have a noisey top end, I've spent some time trying to figure it out and gave up when costs got preventative to trial and error.

 

Mine is not top end, really just between 0-3500 rpm....but only because the engine drowns it out at higher rpm Driving at 1800 RPM, not accelerating, it’s pretty much inaudible. When it happened last time, almost 2 years ago, I recently had an oil change too. Maybe that’s the connection. I don’t need it for my job, so it gets driven about 3-4 times a week, under 20kms each trip usually. In other words, not much. I have heard that oil settling after an oil change may leave the valves prone to tapping but I have no idea. Car drives fine but the ticking is bizarre. Meh, I have Friday off....maybe I’ll just drive by the dealership, have a trained ear listen to it. Thanks for the help

 

Put a batch of 0W-30 oil in it and I bet the ticking will disappear.
In all the cars I had over the years, 5W-30 weight was (is) perfect for the winter. This sucker got noisy in the beginning of each of the last two winters (I bought my car in roughly the same period with you) with 5w-30 in it. As soon as I switched to 0W-30 (Mobil1) the noise disappeared - both times.
I really do think are the lifters.
Strange thing - mine has the noise only in one bank (#2).
Funny (good) thing - 10W-30 (Mobil1 -still) in the summer is thin enough to make it run like butter.

P.S. Drive it more often, at least for 30 minutes daily...

 

Just took it to the dealership and had a mechanic listen to it. He said it its for sure lifter tick. Also said to fix it would be a couple grand more than likely and that he would not bother if he was me as its not something that needs to be fixed, just annoying. *sigh* guess I'll have to live with it and hope it goes away next oil change.

Thanks everyone