Strange hissing noise vacuum leak?

[utilitytristin]

I've noticed when driving around the road, specifically when the car is cold and is warming up to operating temperature there is this hissing noise when I step on the gas.

My regular Explorer doesn't have this issue. The hissing sound goes away when the engine is closer to operating temperature. It happens when the transmission is about to shift gears.

I've attached a video as well, it's kind of hard to hear. Listen closely. Headphones recommend.

 

[peterk9]

It may just be my computer, but I can not play the video.

Peter

 

[utilitytristin]

It may just be my computer, but I can not play the video.

Peter

I'm able to play it on my devices. Try on a mobile device or something. Strange that you can't play it.

 

[peterk9]

I'm able to play it on my devices. Try on a mobile device or something. Strange that you can't play it.

I played it on my phone but could not hear the hissing. Too many other sounds. No headphone available.

Peter

 

[utilitytristin]

I played it on my phone but could not hear the hissing. Too many other sounds. No headphone available.

Peter

The sound is very faint, it's very hard to hear without headphones.