SQ7 Jerks & Rough Idle Points to Crankshaft Issue

I experienced similar symptoms with my 2020 Audi S6. The jerking during acceleration, rough idle, and check engine light pointed to what initially seemed like a crankshaft sensor issue. However, after thorough diagnostics, the real problem was more complex. The main issue turned out to be a combination of failing fuel injectors and a cracked exhaust manifold. The exhaust leak was causing incorrect readings in the oxygen sensors, which made the engine run rich. This created a chain reaction leading to engine misfires and rough performance. The repair required: Replacing all fuel injectors, Installing a new exhaust manifold, Replacing two ignition coils that had worn prematurely, Installing new spark plugs This was definitely a serious issue that needed immediate attention, as the exhaust leak could have caused further engine damage if left unrepaired. The symptoms you describe match closely with what I experienced, particularly the jerking during acceleration. Given the low mileage on your SQ7, this could still be covered under warranty. I would recommend getting a second opinion from a certified Audi dealership rather than an independent mechanic for this specific issue.

Thanks for sharing that experience with the S6. My SQ7 was showing similar warning signs, and I ended up finding that the ignition coils were indeed the main culprit, along with a dirty air filter that was restricting proper airflow. The rough idle cleared up completely after replacing those parts. Did you track the total cost for your repairs? Also curious if youve had any other issues pop up since getting it fixed? These performance engines can be sensitive to small issues.

Had no further engine misfire issues since fixing everything on my S6. The repair bill came to 265 Euro for fixing an exhaust leak they discovered, which was actually causing the uneven engine running. Much cheaper than initially expected, especially compared to the fuel pump replacement they first suspected. The rough idle completely disappeared after the repair, and the engine now runs perfectly smooth during acceleration. I actually think the exhaust leak was causing incorrect sensor readings, making the engine computer adjust fuel mixture incorrectly. A thorough cleaning of the air filter during the service probably helped too. Just keep monitoring for any unusual sounds or vibrations. These engines are quite robust when properly maintained, but early detection of issues helps avoid bigger problems.

Thanks for all your help. I took my SQ7 to a different mechanic who diagnosed the problem properly. The rough idle and jerking were actually caused by defective ignition coils and a severely clogged air filter. Total repair came to 780 Euro including parts and labor. The mechanic showed me how the old air filter was completely packed with debris, restricting proper airflow to the engine. They also found that two ignition coils had failed, which explained the rough running. After replacing these components, the engine runs perfectly smooth again, no more jerking during acceleration or rough idle issues. Really glad I got that second opinion instead of paying for an unnecessary crankshaft sensor replacement. The car has been running great for the past month with no warning lights or performance issues. Learned my lesson about regular maintenance checks, especially for these high-performance engines that need consistent care.