I recently notice an air hiss noise when starting my car cold. Lasts about 45 to 60 secs then goes away.
Anyone had this or know if its a big deal?

 

It's telling you that it's wants you to go away.

I take it your car is a TIP? It's the Secondary Air Pump, it will not affect performance in any way, just make the noise & might throw a cel. The part is $600, & takes about 20min to change out.

 

Yeah, mine is a TIP and does the same thing. I wouldn't really worry about it unless it's throwing codes.

 

Try starting the car and putting it into drive the firstsecond you can. then drive the car kinda hard and see if you still here the noise. I had a leaky sec air..this sounds like the issue but you may not have a leak you may just be hearing the system run...starting and driving hard can stop the system from activating (it did for me)...if you don't have a CEL that is a good reason to not worry just yet...all in all sounds like the secondary air pump..this is to keep the car running clean during start up to lower emissions

 

Yes it is a tipronic. There is a code for oxygen sensor (P0134) previous to hearing this sound. I am going to change those first. This air pump accessable from underneath or from up top?

 

The noise will not go away, it will only get louder.

the pump is at the top side of the Y-pipe on the right side, next to the part on the Y that comes out. It's black & round.