Definition: A trap door-like device on the exhaust side of a turbocharger that limits the amount of boost a turbo can produce. The waste gate consists of a spring-loaded diaphragm. A vacuum hose connects the diaphragm to the intake manifold. When boost pressure starts to exceed the rating of the waste gate, the diaphragm pulls open a bypass flap in the turbo housing. This allows some of the exhaust to go around the turbo impeller which slows it down. A waste gate can be checked by applying pressure to the hose with a hand-held pump. If it doesn't move at the specified pressure, the diaphragm is probably ruptured and the waste gate needs to be replaced.