99 suburban brake/computer problem? HELP!

Discussion in 'Shop Talk' started by centexguy, Oct 18, 2004.

  1. centexguy

    centexguy Guest

    Ill log in when I remember my password. til then I have a problem I hope someone can offer msome advice on. I have a 99 Chevy Suburban with soft brakes that makes a ssssssshhhh air escaping noise which sounds like it comes from under the brake peddal. I have plenty of fluid, no apparent leaks and vacuum hose seems solid into the booster. One weird thing, when I apply the brake idling in park, the engine rpm increases slightly(100rpm) and seems to cut out (miss some)?

    any ideas?
     
  2. moopups

    moopups In Remembrance

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    Power brake vacuum booster diaphram rupture.
     

  3. agmantoo

    agmantoo agmantoo Supporter

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    I will second what Moopups said :)
     
  4. centexguy

    centexguy Guest

    me again, thanks for the responses. I was afraid that might be the problem. I changed one many years ago. As I recall it wasnt too fun or cheap. oh well, I guess Ill start on it tomorrow. thanks again.
    btw how does applying to brake affect engine (the missing) ?
     
  5. centexguy

    centexguy Guest

    me again. the busted diaphram causes a vacuum leak, right?
     
  6. agmantoo

    agmantoo agmantoo Supporter

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  7. wtipc

    wtipc Member

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    I'm having a similar problem with the brakes on a 96 Silverado Pickup, except that my brake pedal is hard. I get the sound of air escaping when I press the brake pedal and my engine runs bad/misfires now. No leaks, plenty of fluid in reservior. I've bled the brakes, but that didn't help much. Please help!

    wtipc
     
  8. Hip_Shot_Hanna

    Hip_Shot_Hanna Well-Known Member

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    same problem only worse ,wtipc, and the same cure, that big pan like thing behind the master cylinder is busted, replacement is the only answer.
     
  9. wtipc

    wtipc Member

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    Thanks, I appreciate your help.