2016 electric motor sound on start-up

[40Man]

As the title says, when I start my 2016, I hear an electric motor like humming sound that lasts for 30 seconds to a minute. I assume it is emissions related, but my 2011 did not do it. Just want to make sure it is a normal thing.

TIA.

 

[hkeller]

It might be the brake booster.

 

[bloc]

The 3UR-FE has pumps that push fresh air into the exhaust manifolds to help the catalytic converters get to operating temp quickly. This is most likely what you are hearing.

They are located behind the front bumper near the slots in the right front inner fender liner. If you go over there while your 30-second noise is occurring it’ll be pretty obvious that’s what is running.

Your 2011 should have had the same system but it’s possible something was different about how the system isolated vibrations from the chassis.

 

[40Man]

The 3UR-FE has pumps that push fresh air into the exhaust manifolds to help the catalytic converters get to operating temp quickly. This is most likely what you are hearing.

They are located behind the front bumper near the slots in the right front inner fender liner. If you go over there while your 30-second noise is occurring it’ll be pretty obvious that’s what is running.

Thanks, I'll check that out and and report back.