SQ8 Power Loss Linked to Faulty Air Temp Sensor

Having dealt with a similar issue on my 2017 S7, I can share my experience as someone with moderate expertise in car maintenance. The symptoms you describe match what I encountered, reduced power, rough running, and check engine warnings. The air temperature sensor malfunction can indeed cause these engine issues, as incorrect temperature readings affect the fuel mixture. My diagnostic steps: 1. Used a diagnostic tool to confirm error codes 2. Noticed inconsistent temperature readings 3. Had visible corrosion on the sensor connections 4. Engine performance would vary with ambient temperature The workshop confirmed the faulty car sensor and replaced the intake air temperature sensor. Total cost was 155 Euro including parts and labor. The fix resolved all symptoms immediately. To provide more specific guidance for your case, could you share: What error codes are you getting? Have you noticed any correlation between outside temperature and performance? Does the problem get worse during cold starts? Are you using a diagnostic tool to monitor the sensor readings? This information would help determine if your issue matches the common air temperature sensor failure pattern.

Thanks for your reply. After checking the error codes with my OBD tool, Im getting P0113 which points to the IAT sensor circuit running high. The symptoms get much worse during cold starts, and the engine issues are definitely more noticeable in colder weather. The temperature reading shows inconsistent values on my scanner, jumping between extremes. Since my last service at 85000 KM, this is the first major issue. Already checked for loose connections but everything seems properly seated. The erratic temperature readings from the car sensor match what you experienced. Based on your feedback, it looks like Im on the right track suspecting the intake air temperature sensor.

Your diagnostic findings definitely align with what I experienced on my S7. The P0113 code, combined with the erratic temperature readings, strongly confirms the intake air temperature sensor failure pattern I encountered. The correlation with cold weather and inconsistent readings from your car diagnostics tool matches exactly how my sensor behaved before replacement. These air sensors typically start failing gradually, showing more pronounced symptoms in cold conditions due to their temperature-dependent operation. In my case, even though connections looked fine visually, the internal sensor components had degraded. After the sensor replacement, my air temperature readings stabilized and all associated engine performance issues disappeared completely. Since your symptoms, error codes, and diagnostic readings mirror my experience so closely, I feel confident recommending sensor replacement. The repair cost should be similar to what I paid (155 Euro), and its a relatively straightforward fix that completely resolved these specific engine performance issues. Based on the mileage you mentioned, this is a typical timeframe for these sensors to start showing problems. Would recommend getting it replaced soon to prevent any potential damage from incorrect air-fuel mixtures.

Thanks for the detailed information. The diagnostic results from your experience really helped confirm my suspicions. Since my last post, I did a few more tests with my diagnostic tool and monitored the intake air temperature readings for a longer period. The sensor continues showing wild fluctuations, especially during the first few minutes after startup. The car diagnostics match the P0113 code pattern exactly, and the erratic temperature reading behavior leaves little doubt. Given that the symptoms, error codes, and sensor behavior align perfectly with your case, I feel confident moving forward with the air sensor replacement. I will schedule the repair this week. The 155 Euro cost seems reasonable for parts and labor, especially considering the potential issues that could arise from running with incorrect air-fuel mixtures. Really appreciate the thorough explanation of your experience, it helped avoid unnecessary diagnostic steps and confirmed the repair path. Will update once the intake air temperature sensor is replaced to confirm if it resolves all the symptoms completely.