Forgot to mention that the van is an 89.

  Hi there:

  Have a question about a possible vacuum leak from the brake booster. When I depress the brake pedal I hear a very low-level hissing sound, coming from what sounds like the brake booster. I have not owned my van for a long time, so not sure if the sound is normal for the vans or if I have a possible vacuum leak. It has pretty much been there since I purchased the van. Braking power is okay, not great, but for what I am told the brakes on these vans are not the best in the world anyway. I just  bleed the lines this past weekend, and the hissing sound is definitely not as loud/strong. So, is this a problem or just normal behavior for the van? FWIW, if I pump up the brakes and then start the van, there is just a small release of pressure, but it does hold. I'm guessing there is a small vacuum leak, but I just don't know. Suggestions?

  Troy