lucman

whats up everybody, Im here cuz I need help diagnosing whats wrong with my car's brakes. Any help would be much appreciated Thanks heres a video of what Im talking about.

Spec R

your underdash needs a wire tuck lol but i bet your stereo bumps hard...

sounds like your ABS pump is freaking out because theres no fluid in it, or way too much air.

check your brake fluid condition/level.

what year is your car? if its 94-97, you can fill up the abs module with a little fluid.

lucman

Yeah I noticed that after I toke this pic and it does bumps pretty hard:driving::rockon::goodjob:... Ok then I'll check the fluid 2morrow.
how do I fix it if it has way too much air? and yes my car is a 95 ls

Line7

You'll need to bleed the lines.

lucman

Just got a reply from some1 else saying Brake master cylinder going out. what you guys think?

pslsnakes

It could be the master cylinder is leaking and letting air into the lines.. Check you fluid and bleed the brakes (best to have a friend help), and if it still doesn't help, look into replacing the master cylinder.

Lynxs1981

I would get the abs checked out. Sounds like it might be trying to engage also.

cruzalekz

this is a brake booster failing. do you still have the brake assist when driving or is the brake pedal pretty hard when you brake?
brake master cylinder will not make noise, air in the brake system will not make noise it will only make your brake pedal spongy,
ill bet $2000 on the brake booster.
good luck

A-series

To test the booster(and it's check valve), turn the engine off and pump the pedal, letting it reach the top of it's travel, a few times. It should, after a couple pumps, start to firm up. Eventually it will be very stiff/firm as there's no longer assist from the booster.

Next, apply moderate pressure to the brake pedal and start the engine. The pedal should sink a little as the booster begins to assist again.

To test the MC - normally only used to test if the MC is leaking internally, but it really tests the entire system from MC down to calipers - turn the engine off and pump the pedal until it's firm (no booster assist), then push down hard (within reason) on the brake pedal and hold it there. It shouldn't sink towards the floor if you hold it there for 15-30seconds. If it sinks significantly and hits the floor, you've got a serious leak, whether it's an internal MC leak or otherwise.

edit: Fwiw, I'm not an expert, but it did sound like the ABS pump was running at first in the video. Later on it sounded a bit different, hard to say. The fact that the sound got louder as you pushed it (you could hear it more muted before he got on the pedal) does seem to point towards it being the booster, though I've never dealt with or heard one that was failing.