ABS Problem, Any Ideas?

[catman]

Hi all, my friend has a Mazda 6 and when he applies the brakes, an awful crunching can be heard and felt through the brake pedal when the ABS operates.

It seems to be coming from the front offside wheel only though and the car stops in a straight line as you would expect.

Any mechanical wizards care to diagnose the problem?
Thanks in advance!

Tim

[mnkiboy]

ABS does make a noise when it's operating. Does the noise only appear when ABS is invoked, or does it happen on every heavy braking application?

[E31Shrew]

eerrr....thats ABS by the sound of it!

[60]

E31Shrew said:

eerrr....thats ABS by the sound of it!

+1

Thats just how it works

[Digby]

Are you talking about ABS on snowy/icey/wet roads, or just driving like a loon and hammering the brakes on to test in the dry?

[Superhoop]

Another vote for 'isn't that normal when the ABS is operating?'

[catman]

It happens on slippery surfaces and only happens on dry roads if you do a really hard stop.

I realise that you get "pulsing" through the pedal, but this just sounds/feels awful. you can feel the crunching, as well as hearing it. I've never had ABS, so I don't know what's ok or not!

I'll tell him that it's ok as everyone has said the same thing, but I didn't appreciate that it would be as bad as that when it's operating!

Thanks

Tim

[2 Wycked]

Sounds like every ABS system I've ever experienced.

[Mafioso]

It's normal.

[DaveL86]

2 Wycked said:

Sounds like every ABS system I've ever experienced.

+1

[Digby]

Had several cars which made all sorts of funny noises and gave odd pedal movements in the snow etc.Was never quite like that in the dry, though.

Even if ABS were to fail, normal braking should still be fine, but it's probably best to get it checked out if you think it really is that loud.None of us have seen or heard it after all and saying it's all ok and then finding his caliper shoots off, may not go down well

Edited by Digby on Sunday 19th December 17:33

[Jayho]

If he wants to avoid it just teach him to plan look as far ahead and plan with more caution to avoid the need to slam on the brakes. Tapping the brakes instead of slamming on usually helps me avoid using to abs...

[morgrp]

You'll find the pedal goes hard and you feel a chatter through the pedal if the abs cuts in. If the ABS is buggered then the car won't use the system and the ABS warning light will come on to tell you it's not working

[WeirdNeville]

DaveL86 said:

2 Wycked said:

Sounds like every ABS system I've ever experienced.

+1

+2

It probably sounds like it's coming from the offiside front wheel because the ABS unit is on the offside front of the cars bulkhead.

ABS generally, skronks, clunks, judders and sounds like the worst plumbing you've ever heard, along with the car juddering as the wheels lock and then turn, and the pulsing through the pedal goes with it.

[catman]

Thanks to you all who have given sensible, informed answers!

You always get one though, who makes ill-informed comments about the driving abilities of people that they have never met.

Where did I say that he goes around slamming on the brakes? All I said was, that if he were to brake hard on a dry road, it would do the same thing.

He merely did this once with me in the car, as a demonstration of the fault on different road surfaces

for the record, I've known him since the 1980's, when we were both Driving Instructors and like me, he has taken and passed several advanced driving tests.

That doesn't necessarily mean that he is going to be familiar with ABS though!

So no, I won't be telling him how to drive, thanks...

Edited by catman on Sunday 19th December 18:05

[GAjon]

My Mazda 6 makes the same horrible noise when the ABS activates, it also seems to be more sensitive to any other car I have had.

[catman]

Thanks, GAjon that's good info! I love Pistonheads!

Tim

Edited by catman on Sunday 19th December 18:25

[jagracer]

catman said:

It happens on slippery surfaces and only happens on dry roads if you do a really hard stop.

If it's doing it on dry roads under heavy braking he may also be hitting a bump or undulation causing one tyre to lose grip slightly and activate the ABS.
First time I discovered how the ABS worked on my car it frightened the st out of me, I thought a wheel was falling off.

[Jayho]

catman said:

Thanks to you all who have given sensible, informed answers!

You always get one though, who makes ill-informed comments about the driving abilities of people that they have never met.

Where did I say that he goes around slamming on the brakes? All I said was, that if he were to brake hard on a dry road, it would do the same thing.

He merely did this once with me in the car, as a demonstration of the fault on different road surfaces

for the record, I've known him since the 1980's, when we were both Driving Instructors and like me, he has taken and passed several advanced driving tests.

That doesn't necessarily mean that he is going to be familiar with ABS though!

So no, I won't be telling him how to drive, thanks...

Edited by catman on Sunday 19th December 18:05

I am not trying to be an arrogant bd who is telling you that you or your friend is a st driver, rather I am informing you on ways you can avoid your ABS going crazy. I've had 3 cars in total, with this one being the only one with very efficient ABS. So I have learned how to drive without the use of ABS and actually dont like going into the ABS.

ABS Is used to prevent your wheels from locking up and there are ways of preventing this yourself without the need to use modern technology, and I am simply informing you how you may manage to to this.

[catman]

I know how ABS works. I drove the car as well, and it comes on at the slightest touch on a slippery surface, such as we have at the moment.

It seems so sensitive, it would be almost impossible to drive around the problem. even coming to a routine stop at a give way causes the symptoms that I've described.

Cadence-braking from a couple of mph seems like over-kill to me.

Tim