Lafesta IAT Sensor Issue

I had similar symptoms on my Lafesta. The IAT sensor reports the temperature of the air entering the engine. If it's faulty, the engine control unit (ECU) receives incorrect data, which can lead to poor fuel mixture and performance issues. Did you check the wiring to the sensor?

I visually inspected the wiring and connectors, but found no obvious damage. Is there a specific resistance value I should be looking for when testing the sensor with a multimeter to confirm it's working properly?

Testing the resistance is a good idea, but the values can vary with temperature, making it difficult to pinpoint without the exact specifications. Given the symptoms and error code, and if the wiring seems okay, the sensor itself is the most likely culprit. I recommend a workshop visit.

Following your recommendation, I replaced the IAT sensor at a workshop. The issue is now resolved. Total repair cost was 155€, including parts and labor.