Is it my brakes or vacuum leak
Do you have brake fluid in the reservoir?
If you lost vacuum it would affect the booster, the brakes themselves are their own system, you would still have brakes but they would be much harder to press. Check the check valve on the booster if you think you have a problem with vacuum. Otherwise check the master cylinder.
Ok thanks we are checking the booster now.
problem is master cylinder on the fire wall or brake calipers if you have rear drums its the cylinders in there. vacuum brake boosters in todays cars work as an assist to do the work of pushing down the brake pedal for you nothing more in fact you can still brake just fine with brake booster disconnected only thing you will have to mash the pedal harder
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