RS7 IAT Sensor Issues Causing Power Loss & Rough Running

I had a similar issue with my 2012 RS6 last summer. Having moderate experience with car repairs, I initially tried cleaning the IAT sensor myself, but the temperature reading remained inconsistent. The symptoms matched yours exactly, reduced power, rough running, and the intake air sensor error code. After attempting basic fixes, I took it to a workshop where they confirmed the IAT sensor was completely defective and needed replacement. The total repair cost was 155 Euro, including diagnostics and the new sensor. The repair took about an hour, and the difference in performance was immediately noticeable. The engine ran smoother, and the check engine light cleared right away. Can you share more details about your car? Current mileage, When did the symptoms first appear, Have you noticed any changes in fuel consumption, Does the problem get worse in specific weather conditions This information would help determine if your air temperature sensor issue matches what I experienced. The IAT sensor is a common failure point on these engines, but its always good to rule out other potential causes. After my repair, I learned its good practice to have the intake air system checked during regular maintenance to catch these issues early.

Just had my car serviced at 46813KM last month, and the symptoms started appearing shortly after. Noticed about a 15% increase in fuel consumption. The car diagnostics definitely point to sensor issues, as the error code matches the IAT sensor malfunction. The problem seems worse during cold starts and damp weather. Really helpful to hear about your experience with a similar engine setup. The repair cost sounds reasonable compared to what I was expecting. Will probably need to have it checked professionally since the basic troubleshooting hasnt resolved the engine issues. Before booking a workshop visit, do you remember if there were any specific intake air system tests they performed to confirm it was the sensor?

Based on the timing of your symptoms right after servicing, this matches my experience exactly. When my RS6 showed similar issues, the workshop performed several targeted diagnostic checks to confirm the air sensor problem. They used a specialized diagnostic tool to monitor the intake air temperature readings in real time while the engine was running at different speeds. The readings were erratic compared to the ambient temperature, which is a clear sign of IAT sensor failure. The increased fuel consumption you mentioned (15%) is almost identical to what I experienced. This happens because faulty temperature readings cause the engine management system to run a richer fuel mixture as a safety measure. The cold start and damp weather sensitivity you described also confirms my suspicion its the IAT sensor. These conditions typically make intake air sensor issues more apparent since the sensor struggles to adapt to rapid temperature changes. One key test the workshop did was checking the sensor resistance values, this definitively showed my sensor was failing. Given your similar symptoms and the car diagnostics pointing to the sensor, you will likely need the same repair I had. Just make sure they clean the entire intake air system during the repair. In my case, they found some residual contamination that could have eventually affected the new sensor.

Thanks for sharing those workshop test details. Makes sense about checking the sensor resistance values, that seems like a good confirmation test. Based on the matching symptoms, especially the weather sensitivity and fuel consumption increase, I am pretty convinced its the same IAT sensor issue you had. Will book it in next week and specifically request they do the real-time temperature reading tests and resistance checks. The complete intake air system cleaning also sounds like a smart preventive measure while they have it apart. Good to have a realistic idea of the repair costs and timeline before going in. Those diagnostic tests you mentioned will help verify if my car sensor problems match your experience exactly. Nice to know it was a straightforward fix that immediately improved performance in your case. Will update once I get the final diagnosis and repair completed. Thanks for walking me through your experience with such similar engine performance issues.