engine dies when braking

[longbedrick]

the engine on the '73 454 dies when I hit the brakes when vehicle is slowing to a stop. I'm guessing vacuum leak. any suggestions? how do you find a vacuum leak?

[joe231]

start your truck let it run for a minute then shut it off with your foot off of the brake. with the engine off, pump your brakes, you should feel 2-3 assisted strokes then it will be very stiff. If you don't get any assist on the first stroke more than likely your booster is leaking(if the vacuum line going to it is good. another tell-tale sign is a sucking sound when you apply the brakes with the engine running...