I have a mk8 Fiesta and I’ve been having having issues with the temps which have been taking way longer than usually to warm up (10+ minutes). As well as the revs hanging at 1.5k on a cold start which do not drop until 10+ minutes. They also do not drop by themselves, it requires me restarting the car then they drop. 

i have the following code come up. Not sure if related…

U0284 - Lost Communication With Active Grille Air Shutter 1 Motor Module

Does anyone know what this could be due to? any help would be greatly appreciated!

Check for wiring damage at the grille shutter plug.  Also check that the grilles can move freely.

I suspect the radiator fan is running constantly if it can't tell whether the shutter is open or closed, and that will increase warm-up time considerably.

On 12/15/2024 at 11:08 AM, TomsFocus said:

Check for wiring damage at the grille shutter plug.  Also check that the grilles can move freely.

I suspect the radiator fan is running constantly if it can't tell whether the shutter is open or closed, and that will increase warm-up time considerably.

Found this wire was unplugged. But not sure where it goes. Is this related to the air grille?

Ambient Air Temperature Sensor

It's just become detached from it's fixing bracket.

On 12/18/2024 at 10:46 PM, unofix said:

Ambient Air Temperature Sensor

It's just become detached from its fixing bracket.

Ah ok thank you. I found this was disconnected too but not sure where it goes. Does anyone know it’s purpose?