Seat Ibiza gasoline engine stalling at idle

That does sound rather bothersome! The check engine light and stalling are definitely not ideal. I am not entirely sure, but have you checked for any obvious air leaks in the intake system? A faulty mass airflow sensor could also potentially cause similar symptoms. Does the engine run rough at all times, or only at idle? I do not have a Seat Ibiza, but I once had a similar issue with another car. Hopefully someone with more insight into your specific model can chime in.

Thank you for your response. Regarding your inquiry about air leaks, I conducted a visual inspection of the intake system and did not observe any apparent breaches or disconnections. However, I acknowledge that subtle leaks may exist which are not readily detectable through visual means alone. Concerning the mass airflow sensor, is there a recommended method for evaluating its performance, or is replacement the only reliable means of verification? The engine's performance is generally smooth across the RPM range, with the exception of idling, during which instability and occasional stalling occur.

Okay, given the stable performance at higher RPMs, but instability at idle, it does sound like the idle control system is the culprit. I am still somewhat skeptical, because there are many things that can cause this. However, based on your description and the error code, a contaminated air intake affecting the IAC valve is certainly plausible. Honestly, without further diagnostic tools, it is rather difficult to pinpoint the exact cause. I would say it is probably best to take it to a trusted workshop for a proper diagnosis and repair. They can perform smoke tests and use diagnostic equipment to verify the issue and provide the necessary remediation.

I would like to express my gratitude for your input. Following a comprehensive inspection by a certified technician, the root cause was indeed identified as a heavily contaminated air intake system, which consequently affected the idle air control valve's functionality. The replacement of the IAC valve and thorough cleaning of the intake manifold resulted in a total expenditure of 425€. The vehicle is now operating as intended, with a stable idle and no further instances of stalling. Thank you again for your assistance.