I believe my brake booster is going bad which is causing a woosh sound when i pump the brake pedal and causes a fluctuation of engine rpm as i pump the brake pedal (like its causing a vacuum leak. Here are a few video examples. Also when the engine is running and i pump the brakes my rpm will drop about 200 rpm and then cause the engine to run rough for a second or two and then it goes back up. Let me know what you think.

http://s446.photobucket.com/albums/q...t=MVI_0487.mp4

 

I must of missed it but & didn't hear anything on the video that you linked. Have you checked the hoses? But it is possible to have it leaking.

 

I have sprayed carb cleaner around all the ends of hoses on it to see if it caused the engine to speed up which it didnt. I have also replaced the vacuum hose which didnt help. The vid has sound for me, you may want to check the volume. I can hear the woosh it makes from inside the cab or under the hood. Sounds like its coming from inside the brake booster.

 

One way to find out is disconnect the vacuum going to the booster & see what happens. Just remember you will be without power brakes so don't go racing off.