Vacuum booster check valve
 

There is a tag on my booster that tells me the warranty is void if the check valve is removed. How would removing the check valve affect the booster and void the warranty?

re: vacuum booster check valve
 

Hi the check valve is so that pressure only goes one way, then there is a relief valve after the check valve, with out the check valve, pressure can go both ways, then you got problem, brakes don't work right or at all, in some places it is against the law to remove TROY

The check valve also protects the diaphragm in the booster from an intake backfire. Without the valve, the pressure pulse could rupture the diaphragm.