Marclor

Hi! I am new to audiworld and have a question for you guys. I've been looking for an answer for a while on various websites and didn't find any useful information so far. I want to apologize for the various english grammar mistakes I will be doing because english isn't my main language.

I own a 2010 audi A5 S-line 2.0TFSI (automatic transmission) and have noticed a weird noise during last summer. I do not know if the noise had appeared earlier because I only started hearing it when I was cruising with my windows down. I can only hear the noise when my windows are down and when I pass beside a wall or a building that will reflect the sound waves toward me.

I would define the noise to be a metallic grinding noise. It will always happen as soon as I release the gas pedal. It might not happen the first 2-3 times I release it after a cold start, and then will always happen. Like you will hear in the video, it will stop as soon as I barely hit the gas pedal again. When I'm cruising and let go of the throttle, it will also temporarily stop while the car changes gear (like when it goes from 3rd to 2nd when decelerating by itself). The noise has not worsen over ~8000km but is still pretty annoying when you just want to take a ride in the city.

A volkswagen mechanic (there is no audi retailer within 350km around me) told me it might be the cat going bad, that a piece of the honeycombs might have broken off. Does that even make sense? Why wouldn't I hear it only in those specific situations? I didn't get any codes or check engine light either.

Thank you!

[vid]https://*******/yFuO/vid]

Marclor

https://*******/yFuO