Boost Turbo Meter Gauge
A boost gauge is a pressure gauge that indicates manifold air pressure or turbocharger or supercharger boost pressure in an internal combustion engine. They are commonly mounted on the dashboard, on the driver's side pillar, or in a radio slot.
Only turbo-charged vehicles will have a turbo-boost gauge. This gauge shows the pressure or vacuum in the intake manifold. More pressure means more performance, but lower fuel mileage. It may also suggest a problem with the turbo-charger. If boost drops, relative to engine RPM, shown on the tachometer gauge, a problem may be developing.