Weird Model 3 white powder underneath car after it rains

That is likely water related, not car related. The water on the concrete is basically pulling (well, technically the term is Efflorescence) minerals from the concrete.

 

I'd call the DEA.

 

Concrete will effloresce over time especially if its a recently poured surface. It's the concrete hardening which happens over years and pulling the water out leaving the minerals (salts) on the surface. That looks like a lot of "salt" as you can even see tire tread marks in it where the tires ran over it. Almost wonder if your friend lives in an area where the roads are salted and the deposits are from that. Like the undercarriage lining has absorbed alot of road water and salts from the wet roadway (you did say after it rained), and after parking the water and minerals drip down onto the concrete floor. The water evaporates leaving behind the salts. Reminds me of our garage back east during the winter. Couldn't wait to hose it out in the spring.

 

I saw a bit of white powder under the edges of my model 3 when I first got it, I assume it was just excess polishing compound washing off. I'm pretty sure that's it (in my case), because I scraped some of it from around the charge port door using my fingernail.

But if it's a substantial amount, I would think it's the concrete as others have said.

 

others here have reported same white powder?

I also have white perf 3,
park exclusively in garage,
haven’t seen rain on paint yet!

yet, I see white dried powder like
substance forward of right front
tire area, to lesser degree under
forward of left front tire area.

this didn’t happen with previous
vehicles parked in same garage,
and garage floor is same same
for last 20 years?

so, in my case, not pulling any
minerals from concrete, it’s something
depositing from model 3 onto floor?

 

The OP title says after rain. This tells me, in his case, that the ground under his garage slab is moist. The moisture rises and brings salts from the concrete. Sometimes if something is left on the slab the slalts will grow in the moist environment.
DaveKR,
If it's been a wet winter in your area, if the drainage has become impaired, groundwater tables have been altered, there is a good chance you are getting salts coming out of the concrete.
Or you have an alien transporting from another galaxy, leaving a bit behind from a faulty transporter.

 

It won't happen every time, the situation needs to be "just right" for that to show. It happens every once in a while in my garage (concrete was poured just under 20 years ago when I built the house), sometimes from moisture falling from the car, sometimes from the hose after I wash the car. I have also seen it on my basement walls - not floor. It just needs to be enough moisture to dissolve the solids then evaporate.

I know it never rains in Southern California, do you use A/C?

 

I live in SoCal and just noticed a line up salt in my garage for the first time. It's been raining here for what seems like a month. The ground is very saturated. Great tip.

 

Tesla magic pixie assembly dust

 

my garage floor is approaching 40 years old
I've lived here over 30 years
this white powder hasn't appeared before
I parked the model 3 in this section of garage.

the white powder only appear under front
section of model 3 forward to front tires.

the white powder doesn't appear nearest to
garage door, where outside moisture exposure
would normally appear first, so I'm calling
horse hockey on the white powder coming
from concrete slab, as it follows the model 3.

 

Is it poetry day here at TMC?

 

Is this your friend? If so, the powder is just @run-the-joules's cocaine.

white powder on the floor underneath of the model 3 parked

 

My cocaine gets around!

 

DaveKR,

It's not surface water, it's moisture coming up from below. The ground under your garage floor might be getting moist from a leaking downspout, landscaping change from a neighbor or any number of ways. Or it really is your ticket, pixie dust is very rare.

 

OK, so splain this lucy...

why hasn't this happened in the
30 years previous to a model 3
being parked in same location
in garage?

now, for sake of argument, why
does this only happen forward of
model 3's front tires? not closer to
garage walls or doors?

nothing has changed except the
car parked over this exact same
concrete, so far now, these explanations
are still horse hockey, as only
variable is the car!

 

switch sides with another car

 

I have an S, so I’m not sure. Does the 3 have hard plastic wheel well liners or the fabric ones? They would trap more moisture than plastic.