Thread: Leaking master cylinder area?

I keep hearing a leaking hissing noise from someplace around where the master cylinder and EBCM are. I have not noticed any issues with braking but if it has been steadily getting worse I possible could not have noticed.

Is it possible to have an air leak someplace on the master cylinder or is it more likely something to do with the brake booster? Is there supposed to be a specific gasket or seal between the two?

Also..Does anything think I leak in that area could cause the car to have a vacuum leak and run lean? I would think if it were the booster it could cause the lean condition.

You are on the right track. There is nothing vacuum-related with the master cylinder itself. You probably have a torn diaphragm in the brake booster causing a vacuum leak, poor power brakes, and possibly the lean condition. Unplug the brake booster line running to the vacuum distribution block on the supercharger and see if the hissing stops. If it does you have found your problem!