Brake booster going out?

Dana67Dart said
I agree withe the gasket and check valve.

You could check with a vacuum pump on the existing parts. If it doesn't hold a vacuum the parts above are cheap.

You could also get a one port check valve

Yeah I'm not sure why it has so many ports. The connector on the intake is a monstrosity with the brake booster and like 5 (!!!) vacuum ports. All are plugged with new nylon caps.