How do i stop a loud noise like a vacunm leak.

you may have a vacuum leak

Depending on the vehicle type, check the power steering fluid. Make sure it's full up to the mark on the stick. If it's full, it's a bad pump.

Sounds like there's a vacumn leak, may be a loose or cracked hose or bad gasket. You should find and repair this asap = dirt is entering the engine thru the leak.

It sounds like a vacumn problem. When the heater controls loose vacumn it defaults to the defrost position. When your car decels your engine vacumn is at its highest. Check your vacumn lines for damage. Check the control panel for a vacumn leak. If you take out the controls and hear a suction noise than the control switch is leaking.

one of the calipers on brakes blew a seal or brake line broke leaking fluid.

difficult one this as without my greasy hands have a look but i would hazard a guess and say it sounds like the air filter on the back of the servo is blocked ,but i cannot place it making a noise when turning the wheel unless its something different ,could even be a vacumn leak somewhere ,to be honest this is a catch 22 question and i would suggest you ask a local mechanic to have a look and post what he says

a lot of the air vents are controlled by vacumn, some auto stores sell cheap stethescopes to help isolate the leak, before you pull the whole dash apart. change the air vent settings , may help isolate it as well

Sounds like you have a major vacuum leak someplace under the hood.Look for any hoses that are broken or came off. You should be able to hear aloud hissing noise if you have a vacuum leak,also could have a intake plenum gasket sucked in or a stuck open EGR valve.

leaking seal on vacum booster where rod from brake pedal enters. will go away until it gets severe