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View Full Version : Brake / ABS problem ?



White
02-12-2009, 10:20 PM
I have 3 issues potentially related to brakes / ABS. Can anyone help as the dealership gives me the run around - they have no clue !

1- When the temperature gets below the freezing point, I get a squeaking sound around 20km/h. That happens everytime the car is cold and lasts less than 1 second. Whether I am in first or second gear it does that sound.

The dealership changed the ABS pump last spring. This winter is worse than last winter. It used to do this when it was very cold only, but now even after filling the car at a gas station it does it. Dealership now tells me that every Mazda3 does this sound.

2- When I brake on an icy road, or on a very snowy road, there is a squealing sound until I remove my foot from the brake pedal. It did this to me 4-5 times this winter. It happened also once on a sunny day where the road conditions were normal - I had to brake as the traffic jammed in front of me.

The dealership could not replicate this and therefore doesn't care.

3- Since the last 2 weeks, I noticed that the braking pedal gets stiff and I need to apply extra pressure on it as the car doesn't slow down. This happened 4-5 times under various conditions (under & above freezing point), but not in icy or very snowy conditions (and therefore doesn't appear to be 'normal' ABS interfering). It did this tonight as I left work. I had braked twice before, but lightly. At a stop light I braked normally, but nothing happened at first. I pressed harder and after a little delay, the brakes worked as if I had slammed them hard. (Not to mention that there was a cop car on the corner - I would have looked like a tool trying to explain that the brakes didn't work !). The car had not warmed up yet, as I had started probably 3 minutes before it happened. When it happened today and in the past, it did it only once, when the car was cold but not necessarily the first time I applied the brakes. Everything then goes back to normal.

I didn't tell my dealership yet, but this is pretty disturbing. I guess that they won't be able to replicate this and I will look like an idiot (again ...).

Are all three problems related ? What is wrong with that car ?

White
02-14-2009, 07:23 PM
No hint & tips, ideas ?

Noisy Crow
02-14-2009, 08:46 PM
How old is your car?

One reason that disk brakes squeal is when they wear to the point that the wear indicators hit the disks. The wear indicators rub when the brakes are NOT being applied (unlike with drum brakes). So maybe that is the problem... the other possbility is that you have metallic pads... they tend to squeak and squeal all the time.

The stiff brakes.... possible hydraulic leak in the brake system, likely the booster. I would check the brake fluid level.

sas
02-14-2009, 09:40 PM
Look here ,how to check booster and check valve.
www.autoshop101.com/forms/brake05.pdf

White
02-16-2009, 06:00 PM
I have a 2008 Mazda with 26,000km.

I doubt the discs/pads are an issue as the noise seems to come from the engine bay.

White
02-16-2009, 06:05 PM
Look here ,how to check booster and check valve.
www.autoshop101.com/forms/brake05.pdf

I doubt I can play with this myself, but this leads to an interesting option with is the booster pump. I didn't think about that one !

2005mazda3
02-16-2009, 07:04 PM
i think you should go to another dealership to check the brake again.
brake is the most important part of the car.:)

sas
02-17-2009, 04:22 AM
The booster uses vacuum created by engine.
You have a tough pedal. It can be faulty booster, mechanically sticking pedal, booster or master cylynder and restriction in hydravlic system.
There are three procedures of diagnosis for booster. All of them easy to perform.
Push break pedal with medium force ,start the engine.Pedal have to fall father. If no then you not have vacuum or you have big leak inside booster or vacuum hose.
Swich off the engine. Pedal have to remain on the same place. If pedal is coming back then you have leak or faulty check valve.

TheMAN
02-19-2009, 05:07 PM
in extreme cold weather, DOT 3 or DOT 4 fluid can thicken up enough that it inhibits proper brake operation, most particularly in ABS cars... I have posted in another thread a while ago about a stiff clutch pedal concern and it is basically the same thing... I recommend replacing the brake fluid with DOT 5.1 fluid to alleviate this issue as it has excellent low temperature viscosity and flows very will through an ABS system