VW Touran IAT Sensor Issues Causing Engine Problems

Having dealt with a similar issue on my VW Golf 2014 petrol engine, I can share some relevant experience. After noticing comparable symptoms, rough running and power loss, the diagnostic tool revealed problems with the intake air temperature sensor. The temperature reading was indeed inconsistent, causing the engine management system to miscalculate the air-fuel mixture. This directly affected engine performance and efficiency. The repair process was straightforward: Full diagnostic scan, Temperature sensor replacement, System reset, Test drive to confirm proper operation Total cost was 155€ including parts and labor. After the fix, engine performance returned to normal with smoother acceleration and no more check engine light. To provide more specific advice about your Touran: Which engine size do you have? Have you had the diagnostic codes read? Are there any other warning lights active? Did these symptoms appear gradually or suddenly? The car sensor replacement significantly improved performance in my case, but its important to confirm the exact cause through proper diagnostics before proceeding with repairs.

Thanks for sharing that experience. Since my last service at 105000km, I've kept detailed records of all symptoms. After reading your reply, I had a diagnostic scan done which revealed code P0113, confirming the intake air temperature sensor malfunction. The symptoms appeared gradually over the past month. Based on your repair cost breakdown, it seems like a reasonable fix. Did you notice any other sensors needing attention during your diagnostic scan? My car diagnostics also showed slightly irregular voltage readings, but the mechanic wasnt sure if this relates to the main IAT sensor issue. Got any tips for checking if the wiring to the temperature sensor is intact before I proceed with the replacement?

Thanks for the additional details about your diagnostic findings. The P0113 code definitely confirms our shared IAT sensor issue, I encountered the same code on my Golf before the repair. When my car diagnostics were run, they actually did show some voltage fluctuations similar to what youre describing. In my case, these readings were directly related to the faulty air temperature sensor and resolved after replacement. No other sensors needed attention. For checking the wiring before replacement: Inspect the connector pins for corrosion or damage, Look for any exposed or frayed wiring near the sensor, Check for proper connector seating, Verify the wiring harness isnt rubbing against engine components My mechanic found the wiring fully intact, and the temperature sensor itself was the culprit. The irregular voltage readings normalized after installing the new sensor. Just be careful when removing the old connector, the plastic can become brittle over time. The gradual symptom progression matches my experience too. The engine management system tries to compensate for incorrect temperature readings, which explains the progressive performance decline. Does your Touran show consistent temperature sensor readings, or do they fluctuate out of nowhere? Mine would jump between extreme values before replacement.

I appreciate all this detailed information about the IAT sensor issue. My Tourans temperature readings definitely show similar unusual fluctuations to what you experienced. Just checked the sensor connector and wiring as suggested, everything looks intact with no visible damage or corrosion. The engine air temperature readings on my scan tool vary between -20 and +80 degrees within minutes, which cant be normal. Based on your experience and the matching symptoms, Im confident proceeding with the air sensor replacement is the right call. Ive scheduled the repair for next week. The quoted price is 170€, slightly higher than what you paid but still reasonable considering current parts costs. Will update on the results and whether it resolves both the performance issues and irregular voltage readings. The car diagnostics should be more conclusive after fixing the intake air temperature sensor. Really hoping this solves the rough running issue like it did in your case.