Whenever I accelerate I hear a kind of hissing sound (something like air leaking maybe??) from the right side of the car. anyone know what this might be? Also, whever I deccelerate, I hear a howling type sound. Are both of these normal? thanks.

 

could be the turbo . . . has it always done this or is this a relatively new occurance?

 

definately the turbo. to most people, my self included, it's music to their ears

 

^^ I wouldn't be as quick to say it's definitely the turbo until we have more information.

Like jdepould asked, is this a new sound or one that's always been there.

I would ask the same for the "howling", and actually, would you also describe this as a whine type of noise? The transmission is known to whine a bit on decel. It's been the same noise(s) in both my '03 and '05 WRX.

 

for what it's worth, to me at least, turbo spool sounds like a turbofan, ie lear jet.