A3 TFSI: Rough Idle Mystery Points to Failed Mounts

As someone with some experience working on VAG cars, I had a similar issue with my 2011 A3 1.8 TFSI. The symptoms you describe match what I experienced, strong vibrations and rough idle pointing towards mount failure. In my case, the problem turned out to be a loose connection in the wiring harness near the transmission mount area. The vibration issues were actually a secondary symptom caused by the engine running rough due to faulty signals. The repair involved checking all cable connections and replacing a damaged plug connector. Total cost was 95 Euro including diagnostic work. The fix completely resolved both the check engine light and the vibration issues. Before assuming mount failure, it would be worth checking the electrical connections first, as they can mimic similar symptoms but are typically less expensive to fix than replacing motor mounts or transmission mounts. To provide more specific guidance, could you share: Any engine codes being shown? Does the vibration change with engine temperature? When did you last have routine maintenance done? Are there any other unusual sounds or symptoms?

My mileage is at 177203 KM. Last service was done about 6 months ago. The vibration issues definitely worsen when the engine warms up. The check engine light is showing error code P0016, which suggests a timing issue between the crankshaft and camshaft position sensors. The mount wear seems to have progressed rapidly over the last month. I can hear a distinct knocking sound from the passenger side when accelerating. I checked the wiring harness area you mentioned but all connections appear secure. Given the P0016 code and the defective engine behavior, I am starting to think this might be more than just a failed mount issue.

Thanks for providing those additional details. After reading your symptoms and considering the P0016 code, I need to revise my initial thoughts about this being primarily a mount-related issue. While my A3 did show similar vibration symptoms, the P0016 code you are getting typically points to timing-related problems rather than mount failure. When I dealt with my mounting bracket issues, I never got timing-related codes. The knocking sound from the passenger side could still indicate a damaged transmission mount or rubber mount, but I would prioritize investigating the timing system first. In my case, the mount wear was a secondary issue that developed due to excessive engine vibration from other problems. Key points to consider: P0016 often relates to timing chain stretch or tensioner issues, The 2.0 TFSI engines are known for timing chain problems around this mileage, While mount failure might be present, it is likely a result rather than the cause, The warm engine symptoms suggest timing chain issues I would recommend having the timing chain system checked before replacing any mounts. My repair costs for the full timing chain service ended up at 1200 Euro, but yours might vary depending on what components need replacement.

I appreciate everyone's detailed input on this. After hearing about the experiences with similar engines and the timing chain issues, I am convinced I need to prioritize getting the timing system checked before focusing on the mount failure symptoms. The combination of the P0016 code, increased vibration issues when warm, and the knocking sound does match up with what others have described as timing chain problems. The defective engine behavior getting worse over the past month also fits this pattern. I will schedule a thorough inspection of the timing chain system first, keeping in mind the potential 1200 Euro repair cost mentioned. While the motor mount and vibration issues are concerning, addressing the timing chain seems like the more urgent fix based on the feedback. Thanks for helping me understand that the mount wear might be more of a secondary issue resulting from the timing problems. This discussion has definitely saved me from potentially focusing on the wrong repair first. Just booked an appointment for next week to have the timing chain system inspected. I will update once I know more about the extent of the timing chain wear and whether any motor mounts need replacement as well.