Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

2018 Toyota Prius - Sound help

Every once in a while I go into my garage at night and hear a sound similar to air being let out of tires coming from the rear of the car. Of course, the tires never deflate. I would also occasionally hear this on my prior car, a 2006 Corolla. Any idea what this is? Thanks

My guess would be it is a sound from the fuel vapor management system.


The Owner’s Manual for my friend’s Rav-4 mentions the “normal” noise from the periodic self-test of the vehicle’s Evaporative Emissions system. That self-test is run after the vehicle has been idle for several hours.

I would be surprised if the Prius Owner’s Manual didn’t mention this situation.
Has the OP perused that manual?

1 Like

Surely you jest. :rofl: