Wiper fluid works when cold but not when hot?

hyundai
sonata
fluids

#1

I have a 2007 Sonata. It is freezing outside now, and when I first get into my car the wiper fluid comes out just fine, but after my car warms up it does not come out at all. All other discussions I have found apply to the opposite, and no doubt more common, situation of ice buildup in the lines and then thawing when the car warms up. Is there something that could be expanding when the car gets hot and pinching the line? I do not have this problem in the summer.

FYI: I know pretty much nothing about cars.


#2

Do you have “winter mix” in the system? If not, you need to purge the system and refill it with winter mix. I keep it in all year around.

What might be happening is that once you hit the pump it fills the lines to the sprayer heads and that fluid is freezing. Then, when you shut down, the fluid makes its way back to the fluid reservoir. The temperature must be just about at that freezing point.

Water always freezes from the surface down because that’s where the heat is most readily lost. That fluid in the tube is where your wash fluid’s residual heat is most readily lost.

Post if something I’m saying makes no sense. Like all theory, I’ve made some assumptions here.


#3

I think mountainbike is probably about right - you start with empty lines and all fluid in the reservoir. The pump is probably down low where nothing is frozen. You use it, fill the lines and spray head and those contain little fluid and are exposed to the freezing air that they then freeze up. I can’t think of anything else and that makes sense.