Twingo temperature issues check engine light

I had a similar issue with my Twingo. Have you checked the fuse for the active grille shutter system? The active grille shutter is a system that opens and closes vents in front of the radiator to control airflow and improve fuel efficiency and engine warm-up times. If the fuse is blown, the shutters might be stuck closed, restricting airflow even when the engine needs cooling. That could explain the temperature issues and the slow warm-up.

A fuse for the grille itself? Wow, I didn't even know that was a thing! Where exactly would I find that fuse? And would a blown fuse really cause the check engine light to come on? I thought that was only for major engine malfunctions.

Yes, it's part of the active grille shutter system, designed for fuel efficiency and faster warm-up. The fuse box location should be detailed in your owner's manual. The check engine light is triggered because the engine control unit (ECU) detects that the grille shutters aren't functioning as expected, indicating a potential problem with engine temperature regulation. While a blown fuse is the simplest potential cause, I recommend taking it to a trusted workshop to ensure a more accurate diagnosis.

You absolute legend! Turns out it WAS the fuse! A quick trip to the auto parts store, 52€ lighter, and we're back in business. New fuse, problem solved! The temperature readings are normal, the check engine light is gone, and it warms up in no time. Thanks a million!