Humming noise?

[Amish Electrician]

So I was oulling my car into the detail bay at my work and i got out to open the bay door to drive in and all of a sudden my ls starts making this very loud humm noise its coming from somewhere under the hood i have no clue what it is and it has done this a couple times before but everytime it seems to go away after 10 secs but it is very loud and im just kinda concerned????????????????????????????????????

 

[FALECF4]

Could be your fan kicking it high because you are idling. They get pretty loud!

 

[97stscaddy]

Cooling fan.

 

[The Hotness]

I have never heard my fan. Hi or low. :/

I thought maybe it was the 24 foot glasspacks he has that would cause a pretty good hum!

 

[PetesSweets86]

I have never heard my fan. Hi or low. :/

I thought maybe it was the 24 foot glasspacks he has that would cause a pretty good hum!

Or his mother in the back seat