2 problems...

[e30 gangsta]

Well first is when i turn off car i hear hissing by the brake pedal. Like air hissing. Then with 1 or 2 pumps of the brake pedal it goes away.

Also sometimes i drive my car and i punch it and it like stalls and misfires. As if it is missing on a cylinder or something. Any ideas?

Im going to run a can of sea foam. Also im going to change my cap and rotor.

[kowalski]

well the vacume leak might be your problem. either the diaphram in your brake booster is cooked or the 1way valve on the brake booster line is cracked or the seal to the brake booster check all your vacume lines the little plastic valve, and if it still does it get your booster checked.

[e30 gangsta]

u think it could be the fuel filter? for problem #2? And what little plastic valve?