So i pull into my garage after about a two minute drive from a friends house (started the car there) and there is a steady hiss sound coming from in the engine bay. i've dertermined the general area from which it's coming is to the left of the engine and like under the alternator..... any ideas? .... anyone else? this is the first time i've heard this.

 

How old is the car?
Isn't it because the engine was overheated? (long drive)
give us more info :D
thanks

 

it was a 2 minute drive. and im guessing it cant be that old because its an 06 white si.

take it to the dealer

 

Sounds like the usual AC sound to me...

 

My old type r did this too.....100% normal

 

I always thought it was the intake making the slight hissing noise. It's completely normal though.