

What is this plug?
I'm working on replacing my deteriorating air deflectors hoping that it will help with my ac not working great while sitting still. (I just had the whole system replaced, works great while moving or parked with a fan in front of it).
While doing so I found this plug. It looks like it originally fed in between the condenser and the radiator. (I pulled it in front of the condenser for the photo) Is this possibly a plug for an electric fan with a stopper installed? Or, as the end piece looks threaded, is this some sort of sensor that should be screwed into something?
I have a 2001 V10 4x4.