No, not that itty-bitty little gauge that tells you if the vacuum pump has failed...
Does anyone know of a link that describes the difference between a manifold pressure gauge as used in an aircraft and a vacuum gauge as used by every engine mechanic in the world, other than the scale and the direction the needle spins to indicate greater vacuum? (And, I suppose, the $$$ needed to certify the thing for aircraft use.)
What I'm wondering is if the manifold pressure gauge is as useful for diagnosing engine problems as a vacuum gauge, ie, does the pointer indicate less vacuum if the rings are bad, or jump around 4"Hg or so if a valve is sticking, and so on. I've never flown a constant-speed prop plane so I have no experience with the instrument.