Engine off - noise from rear area

[LBridges]

Just came back from the garage and there is a sort of fan noise coming from somewhere in the rear area of the LC. Pretty used to hearing down-time noises from the wife's Avalon hybrid, but first time coming from the LC.

Vehicle last ran about noon today and noise noticed around 10:30 PM.

Might have investigated more but I was in my boxers and didn't want to raise the door. So I came in to search the forum and see if it had already been discussed/dismissed. Tried three different searches and nothing came up that seemed like this issue.

This is the only time in 2 years of ownership I've ever heard this (maybe I should pay more attention?). Any clues, things to check?

And of course, my apology if I missed an obvious thread that covered this.

 

[bloc]

Normal.

It is some kind of pump associated with evaporative emissions. This comes up every few weeks.

 

[LBridges]

thanks, that was my hope.

 

[Rigger]

Yes. Normal.

 

[Hammeredsole]

It pressurized the tank and does a leak down test. You can hear the motor strain a bit near the end as the pressure rises. It runs the rest a few hours after shut down. If it fails, a CEL will come on next time you start the truck.