KIA SPECTRA- makes hissing noise

I have a 2007 KIA Spectra and it makes a hissing noise when I start to break. I took it into the dealership and they say nothing is wrong and these cars are just thsi way.

I have a bumber to bumber warranty so I think this is why they say nothing is wrong. Can anyone help me??

Did this just start happening? The power brake booster could be bad. Any problems with braking?

If supposedly “they all do it”, have them show you by giving you a ride in a comparable vehicle and demonstrate this for you. Did you have someone ride along with you in your car to demonstrate the noise?

The brake booster is the first thing that came to my mind too. It’s a vacuum operated diaphragm that assists you in applying the brakes. It uses the vacuum from the engine.

Follow NYBo’s advice, have them prove it’s normal on another of the same vehicle. Also again as NYBo said, take their shop manager (NOT the service advisor) along for a ride and show him the noise.