Something's wrong with my brakes. Help?

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Discussion Overview

The discussion revolves around brake issues in a 1992 Chevy Lumina sedan, specifically concerning soft brakes that require pumping for responsiveness and a malfunctioning emergency brake. Participants explore potential causes and solutions, including mechanical and hydraulic aspects of the braking system.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant describes the brakes as soft and requiring pumping to achieve responsiveness, noting a sound of air escaping while pumping.
  • Another suggests that a leak may be present and questions the brake fluid level, while a later reply confirms that the fluid level is always fine.
  • Some participants propose that trapped air in the brake lines could be causing the issue, recommending that the brakes be bled properly.
  • One participant mentions the importance of following the specific bleeding procedure for the vehicle, especially if ABS is involved.
  • Another participant notes that the emergency brake's poor performance might indicate underlying issues affecting both braking systems.
  • There are suggestions to check the rear brakes and adjust them if necessary, although one participant clarifies that the vehicle does not have drum brakes.
  • A participant shares a method for bleeding brakes that involves using a jar and tubing, recalling their own experiences with brake issues in the past.
  • Some participants speculate about the possibility of a mis-sized rotor or a vacuum leak affecting the braking system.
  • Another participant mentions that anti-lock brakes were an option for this model and that they require a specific bleeding sequence.

Areas of Agreement / Disagreement

Participants express multiple competing views regarding the cause of the brake issues, with no consensus reached on a definitive solution. Various hypotheses are presented, but uncertainty remains about the exact nature of the problem.

Contextual Notes

There are limitations in the discussion regarding the assumptions about the vehicle's braking system, including the presence or absence of ABS and the specific configurations of the brake components. The discussion also reflects varying levels of familiarity with the vehicle's mechanics among participants.

  • #31
dlgoff said:
What you are hearing is the power/boost(assist) vacuum leaking. It's what the master cylinder is attached to. Between your foot and the master cylinder.

http://www.cardone.com/English/Club/Products/Brakes/Protech/Images/930393e.gif

This would have been my first guess as well...but that doesn't explain the e-brake not working well.

Unless one came before the other? Or they both happened at the same time, but that is a bit unlikely.

I may have missed this, but did they both happen at the same time? Or was the e-brake like that before and maybe you didn't notice because the rest of the brakes were working fine?
 
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  • #32
erok81 said:
This would have been my first guess as well...but that doesn't explain the e-brake not working well.

Unless one came before the other? Or they both happened at the same time, but that is a bit unlikely.

I may have missed this, but did they both happen at the same time? Or was the e-brake like that before and maybe you didn't notice because the rest of the brakes were working fine?

I've had the car for about four years. They have both always been like that the whole time I've had it.
 
  • #33
erok81 said:
This would have been my first guess as well...but that doesn't explain the e-brake not working well.

Newai said:
I've had the car for about four years. They have both always been like that the whole time I've had it.

Well, most emergency brakes I've seen only apply to the rear wheels. And they aren't really meant to stop your car like the hydraulic system is designed to.
 
  • #34
dlgoff said:
Well, most emergency brakes I've seen only apply to the rear wheels. And they aren't really meant to stop your car like the hydraulic system is designed to.
Yep! Maybe I'm really used to older vehicles, but most emergency brakes in my trucks/cars were cable-operated tensioners that engaged the rear brakes mechanically. Not really enough to stop you if your vehicle has any momentum, but enough to stall out your engine if you dump the clutch with the EB engaged.
 
  • #35
Newai said:
I've had the car for about four years. They have both always been like that the whole time I've had it.

Doesn't the US have any mandatory safety inspections, like the UK "MOT test". The name is an anachronism now, because the Ministry of Transport doesn't run they system any more - it's an annual inspection of the safety related components for all vehicles, starting at 3 years old.

You wouldn't be able to tax or insure a car more than 3 years old with faults like that in the UK, and if it was picked up by a numberplate recognition camera while being driven untaxed/uninsured you would probably get a visit from the police not long afterwards.
 
  • #36
Well, it's been fully inspected at three different places so far.
 
  • #37
Newai said:
Well, it's been fully inspected at three different places so far.

Have you had your leg inspected?
 
  • #38
lisab said:
Have you had your leg inspected?

Only my head per the demand of several coworkers. I don't have any cats around handy, so the leg inspection will have to wait.
 

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