Open hose under the hood, looks like leaking beneath

Can anyone tell me what this reservoir is for? I'm just now noticing an open hose hanging off to the left side, and there looks to be some chemical residue beneath it. Is this a problem? I don't see any where around it that it used to connect to?

The tank that the hose is attached to that is on the right (front of the car) is the coolant tank.

Yes I think I figured out it is the coolant tank. But is it normal to have am open hose just hanging off the end of it like that? Can anyone else confirm with their own car?

^^^
Yes. Mine is just like that. I’m assuming it’s for overflow reasons.

Mine also has some crusty bits around the outlet and some deposits on the hose attached to the PDM stack.

Will try to attach a pic later.

Good to know, what a relief. Thanks!

It's the coolant reservoir. In case the pressure exceeds the rating of the cap, the hose is meant to carry the overflow. Yes, it's just open on one end. The reservoir may have been overfilled at one point, or coolant may have gotten hot enough that it expanded and overflowed. I wouldn't worry too much as long as the coolant level is ok and you don't keep having leakage.

If you have persistent leakage there and are losing coolant, inspect the cap for proper fit (when the system is cold!) and make sure the seating area is clean. Pressure caps can develop a leak. Easy enough to replace with a new one if it's not holding pressure. I guess it's possible to have overheating problems but I've never heard of it in this vehicle.

Attached pic of mine.

Looks mostly similar. Thanks for all the helpful insight everyone!

It doesn't seem great to just dump antifreeze at the top of the engine bay. It will eat paint... And maybe some gasket materials.

On most motorcycles, the coolant overflow is carefully routed all the way down near the kickstand, so it doesn't make a mess.

specialgreen said:

It doesn't seem great to just dump antifreeze at the top of the engine bay. It will eat paint... And maybe some gasket materials.

On most motorcycles, the coolant overflow is carefully routed all the way down near the kickstand, so it doesn't make a mess.

Click to expand...

Perhaps for aesthetics, but also I'd imagine it's to keep boiling-hot coolant from coming into contact with the rider. Should be fairly innocuous to the rubber, metal and plastic materials in the engine bay. It's brake fluid that eats paint with abandon.

But I did have one car where the coolant overflow sprayed directly onto a connector for the electric power-steering so I did get a longer hose in that case. ICE engine bays are usually temples to grunge, but in an EV, the coolant residue does seem unnecessarily messy

Looks like a job for... COOLANT OVERFLOW COLLECTION BOTTLE MOD!!!