Charge Sensor Failure Causing Power Loss & Whistling

I experienced a very similar issue with my 2013 Subaru Trezia, which shares many components with the Justy. While I have some experience with basic car maintenance, I relied on professional help for this specific problem. The symptoms you describe, whistling noise, power loss, and the engine sensor warning, match exactly what I encountered. The airflow sensor readings were erratic due to a loose connection in the wiring harness near the air intake system. The temperature fluctuation readings were throwing off the engine management system. My mechanic found that the charge air temperature sensor connector had developed a poor contact due to vibration and heat cycles. The fix was straightforward, they cleaned the connector pins and secured the wiring properly. Total cost was 95€ including diagnostic time. After the repair, both the whistling noise and power issues completely resolved. The check engine light cleared and hasn't returned. To provide more specific advice for your case, could you share: current mileage on your Justy? Any recent work done on the air intake system? Does the whistling noise change with engine speed? Have you noticed any changes in fuel consumption?

Last service was at 28683 km when they checked the automotive sensor system. In my case, the mechanic inspected further and found that the air temperature sensor was not the only issue. The intake manifold gasket had a small leak causing the whistling. After replacing both the temperature gauge and gasket, my power returned to normal and the whistling stopped. The engine sensor warnings cleared immediately. Make sure they check for vacuum leaks around the intake, it might save you from replacing parts unnecessarily.

Thanks for sharing those details about your repair experience. Your situation actually mirrors what happened with my Trezia after the initial connector fix I mentioned. While cleaning the connections helped temporarily, I also ended up needing a manifold gasket replacement when the symptoms returned. The automotive sensor system can sometimes mask underlying vacuum leaks, which is exactly what occurred in both our cases. The air temperature readings were inconsistent because the leak was affecting the sensor data. After getting both issues fixed, the temperature sensor connection and the manifold gasket, the engine performance returned to normal. The cost for my complete repair ended up being 380€, covering both the gasket replacement and fixing the sensor connections. The airflow sensor now shows stable readings, and the temperature fluctuation issues have completely disappeared. For anyone else reading with similar symptoms: make sure your mechanic performs a thorough vacuum leak test before assuming its just a sensor issue. The combination of whistling noises and erratic engine sensor readings often points to multiple related problems in the intake system.

The complete repair on my Justy fixed all issues and confirmed what you experienced. My mileage is now at 31000 km, and the engine sensor readings have remained stable since addressing both the air temperature sensor and manifold gasket. The whistling noise completely disappeared after the intake manifold repair, showing how the automotive sensor warnings can sometimes point to larger underlying problems. The total repair cost was 425€, but the improved performance and fuel economy made it worthwhile. The charge sensor now gives consistent readings, and the engine runs like new. Definitely worth having the mechanic check both the airflow sensor connections and potential vacuum leaks when these symptoms appear together.