I've notice quite a loud vaccum leak at the number one intake manifold position. It's just below the manifold, I put my thumb in that recess below the manifold and the leak stops. So I'm guessing that a piece of the gasket cracked and fell off or got sucked in. My question is, short of pulling the manifold and doing the job right, is there something I can do in the interm that will not harm any of the sensors? I thought about high temp RTV but a friend told me this is a bad thing as the silicone will destroy the O2 sensor. Any ideas?

TIA