Q7 TDI Rough Idle Points to Engine Mount Issues

The symptoms you describe match what I experienced with my 2016 Audi Q5 TDI. A worn engine mount was causing excessive vibration during idle, accompanied by the check engine light. The rubber mount had deteriorated, allowing too much engine movement. The mounting bracket showed clear signs of stress from the excess vibration. When the mechanic performed diagnostics, they found the engine mount wear was actually a secondary issue. The primary problem was a faulty wiring connection to the engine sensors, which caused both the vibration and check engine light. The repair involved: Replacing the damaged wiring harness connector, Installing new engine mounts as preventive maintenance, Recalibrating engine management system, Full diagnostic scan to ensure no residual issues This was a serious repair requiring specialized diagnostic equipment. The defective engine mount needed replacement anyway, but fixing the electrical connection resolved most symptoms. The repair took about 6 hours total. Would recommend having both issues addressed simultaneously since the labor overlap makes it cost-effective. These symptoms should not occur at such low mileage, so having it properly diagnosed and documented is important for warranty purposes.

Thanks for sharing your experience with the engine mount issue. I had nearly identical symptoms with my Q7 last year, and the fix really helped eliminate those annoying vibrations. The transmission mount also needed replacement once they got in there. Did you remember roughly what the total repair cost came out to? And has everything been running smoothly since the failed mount was replaced? My repair was several months ago but I keep a close eye on any new vibrations just in case.

Just wanted to update on the repair costs since fixing that engine mount issue. The total came to 95 Euro for fixing the faulty wiring connection that was causing the vibration issues. The mechanic identified the root cause quickly and got it sorted. My Q5 has been running perfectly smooth since the repair. The original rubber mount problem was actually caused by that bad electrical connection putting extra stress on the mounting bracket. Once they fixed the wiring, all the vibration issues completely disappeared. The transmission mount was inspected during the repair but showed no signs of mount wear, so no replacement was needed in my case. Always good to have them check all mounting points while they are working in that area though. Been about 8 months now with zero vibration problems. Regular maintenance checks are still important, but that repair definitely resolved all the concerning symptoms we discussed earlier.

Thanks for the advice. Finally got my Q7 back from the shop yesterday. The total repair came to 850 Euro, which included replacing both the engine and transmission mounts, plus fixing that wiring harness issue. The mount failure was actually worse than expected once they got in there. The rubber had completely separated from the mounting bracket, which explained the severe vibrations. The mechanic showed me the defective engine mount and it was obvious it needed replacement. After just one day of driving, the difference is remarkable. No more vibration at idle, check engine light is off, and the whole car feels more solid. Going to a different shop this time really paid off, they actually took the time to properly diagnose the issue instead of just guessing. Still planning to monitor things closely over the next few weeks, but so far extremely happy with the repair. Worth every cent to have it fixed properly and get rid of those concerning symptoms.