Nissan Repair: truck, brake master cylinder, engine vacuum

Question
no brake and when pumping brake it wants to stall

Answer
Hi Allen -

Did not get your vehicle info, such as year, make and model, but I am assuming you have engine vacuum assist brakes.

When you say "no brakes", is the pedal hard to push down on? If so,
looks like you power booster has gone bad. Quick test for this is to remove the hose that enters the booster (this is the 3/8" line that goes into the round cylinder behind you brake master cylinder). Plug the hose and start the engine. Press the brake and if the engine runs smoothly, then the booster needs replacement.

The booster sometimes goes bad because of a leaking master cylinder. If you see a trail of brake fluid where the master is connected to the booster, or if you are adding brake fluid often, then replace the master cylinder as well.

Sometimes there is a deal where you can buy both together. Do some shopping.

Hope this helps -
aloha
calvin