RS4 Boost Issues: Faulty Charge Air Temp Sensor Alert

I faced a similar issue with my 2018 RS5, and being someone with moderate experience working on cars, I can share what worked for me. The symptoms you describe match exactly what I encountered, the air intake system was showing irregular temperature gauge readings, and the charge sensor was giving false readings. After some basic troubleshooting, I took it to my workshop where they found a loose connection at the sensor plug. The fix involved checking all cable connections around the automotive sensor area and replacing one damaged connector. The temperature fluctuation issues disappeared completely after the repair. Total cost was 95 Euro for diagnostics, parts, and labor. The whistling sound you mention could indicate additional issues with the air intake system. Before proceeding further, could you provide: Exact error code from the scanner, When did the symptoms first appear, Any recent maintenance or repairs, Current mileage, Weather conditions when the issue occurs This information would help determine if your case matches mine or if there might be other underlying issues to address.

Thanks for the detailed response. My current mileage is 50714 KM, and the last service was done just 2 months ago. The error code from the scanner is P0113, and the symptoms started about a week ago. The whistling noise becomes more noticeable when the air temperature outside changes significantly. The automotive sensor readings show inconsistent values especially during cold starts. I checked the connections around the charge sensor area as you suggested, but they seem tight. Could a faulty temperature sensor itself be the issue rather than just loose connections? The air intake system otherwise looks clean and properly connected. Would it make sense to replace the sensor first before looking into more complex issues? Based on your experience, is this something that could get worse if not addressed promptly?

I understand your concern about the P0113 code. Since my RS5 repair, I learned that the air temperature sensor itself can definitely fail independently of connection issues. After fixing my initial connection problem, I actually had the same error return 6 months later. This time it was the sensor that failed completely. The automotive sensor replacement cost me 180 Euro, but it solved all symptoms permanently. A few important points from my experience: The temperature fluctuation readings worsened over time, Ignoring it led to reduced fuel efficiency, The air intake system performance kept declining, Cold weather made symptoms more noticeable Based on your description and my similar case, replacing the sensor seems like the logical next step. The inconsistent readings during cold starts strongly point to a failing air sensor. The whistling noise correlation with temperature changes also matches what I experienced before the full replacement. The repair is straightforward, most workshops can complete it within an hour. Just ensure they use OEM parts for the air temperature sensor to avoid future issues. Since your symptoms mirror my second encounter with this problem, I would recommend addressing it soon to prevent potential damage to other air intake components.

Thanks for the input. After reviewing the responses and comparing with my situation, I think I'll go ahead with replacing the temperature sensor. The matching symptoms, especially the correlation between the whistling noise and air temperature changes, make me confident this is the right path forward. Getting it done soon makes sense to protect the rest of the air intake system. The cold start issues and inconsistent automotive sensor readings are concerning enough that I dont want to risk further problems. Will make sure to request OEM parts for the replacement. The 180 Euro cost estimate helps with planning. I will schedule an appointment with my regular workshop this week and have them check for any additional air intake system issues while they replace the charge air temperature sensor. I appreciate the detailed experiences shared here, they have been invaluable in understanding what I am dealing with. Will update the thread after the repair is completed in case others encounter similar engine sensor problems in the future.