Air hissing when brake pedal is pressed

[jruppert]

I would appreciate it if someone could shed some light on me with this problem. I am getting some air hissing while pressing on the brake pedal. I did a search and come up with a bad brake booster. The air is coming out from the valve that is mounted at the brake pedal. The air hisses when the valve is released outwards. It was my impression that this valve is bad. Am I wrong?

 

[customperforman]

Mine is doing this too, it only seems to do it when its below zero . Now that it was above 15 deg 's today it didnt make the sound. I need to look into it also. Mine doesnt always make the hissing sound when the brake pedal is pressed.

 

[jruppert]

I know its coming from the valve. I removed the valve from the bracket to which it sits against the pedal. With it removed, you can press the pedal and no hissing sound. But you can take the valve and let it outward and hear the air coming out.

 

[sho'd]

dosn't that have something to do with the automatic e brake, i can't remember??

 

[jruppert]

This is a thick vacuum line that runs from the firewall and down to the pedal. At the end of the line there is a valve that is approx. 1.5 inch. At the end of the valve there is a white plastic piece that moves with a spring inside. This is what sits against the pedal. This is where the air is leakin out.

 

[jelloslug]

That is part of the cruise system and AFAIK it's normal.

 

[RaJ93]

my car has been making that noise since its fallen below 0 here.

 

[jruppert]

I dont see how it can be normal. It sounds like a freakin vacuum leak when pressing the brake.

 

[jruppert]

I found out that this is called the speed control dump valve.