Here's the problem..

1. At a stop, when the car is either cold/warm, pushing the brale pedal produce a hissing noise inside the cabin.

2. Pedal is really firm, like no assist is available..

3. When the brake pedal is pressed at a stop, the car shudders and want to die...

4. No leak, brake fluid is ok, have been changed last year...

What would be the problem??

Thanks,

Guy

Possibilities:

Hoses/check valve:

1. Bad hose between intake manifold and check valve

2. Bad hose between check valve and booster

3. Leaking check valve

Booster itself:

4. Dislodged reaction disc

5. Leaking push rod seal

6. Leaking between valve body and seal

7. Leaking valve plunger seat

8. Bad diaphagm

1-4 can be repaired/replaced the rest would require a new booster.

Was checked this morning.. brake booster busted..

Will need a new one..