Audi S4 Rough Idle Points to Failed Engine Mount Fix

Had similar symptoms with a 2016 A4 2.0T. The rough idle combined with check engine light pointed to motor mount failure on the passenger side. The rubber mount had deteriorated, causing excessive vibration issues at idle and during acceleration. The mounting bracket showed clear signs of wear during inspection. The technician performed a thorough check of all three motor mounts, as they often fail in sequence. The diagnosis involved visual inspection and load testing of each mount while the engine was running. This was a serious issue requiring immediate attention, as failed motor mounts can lead to misalignment of other components and potential damage to transmission connections. The repair involved replacing both the front and passenger side mounts since they work as a system. The vibration completely disappeared after replacement. Important to note that low quality replacement mounts can fail prematurely, using OEM parts is crucial for this repair. Having seen both vehicles with the same symptoms, mount failure is a common issue in this engine family when reaching 50-70k km.

Thanks for sharing. I had that exact issue on my S4 last winter. The defective engine mount caused serious vibrations, especially at stoplights. Got all three mounts replaced since the transmission mount was also showing early wear signs. Were you quoted for all mounts or just the failed one? My repair was not cheap but definitely worth it, the car feels solid again. Curious about your costs and if youve noticed any other issues since the fix.

Just got back from the mechanic today actually. Unlike your case, my engine mount issue was mainly caused by a faulty cable connection rather than the mount itself. The repair was relatively inexpensive at 95 Euro for fixing the connection, which was causing the monitoring system to misread the mount status. The engine mount that initially appeared defective was actually in good condition once they sorted the electrical component. Pretty relieved since a full motor mount replacement would have been much more expensive. They did inspect all mounting brackets and the transmission mount during the diagnostic process just to be thorough. Since the repair, the vibration issues have completely disappeared and the engine runs smooth as new. No check engine light or other problems have surfaced. Really glad I got a second opinion on this one since replacing all the mounts unnecessarily would have been quite costly. The failed mount symptoms can sometimes be misleading, worth having a thorough electrical check before jumping to full replacement. Running perfectly now for about 3000km since the fix.

Had my S4 checked today. The motor mount diagnosis revealed two completely failed mounts and the transmission mount showing early wear. Total repair came to 850 Euro including labor, which was steeper than expected but worth every cent. The shop found the rubber mount on the passenger side had completely deteriorated, explaining the harsh vibrations. They recommended replacing all three mounts since they typically wear as a set. Smart call since the front mount was also damaged. The repair took about 5 hours. They showed me the old mounts, the rubber was cracked and separated from the metal. Since the fix, the car feels totally different. No more vibrations at idle, and the engine sits solid. Really glad I got it sorted before it caused more issues. Definitely keeping an eye on any future mount wear, but for now, everything is running perfectly. The investment in OEM parts should keep things stable for another 50k km at least.