ABS pump noise at low speeds or slowing to a stop

[corrado g 0]

Hi my ABS pump is making a noise as in its trying to activte the ABS and the brake pedal stiffens too. The light goes out on start up so its not the sensors or rotors, any clues to what is causing this? Is it supposed to be like this? Thanks.

[Supercharged 2]

Check thge ABS ECU for water damage...

[corrado g 0]

The ABS unit is apparenly working ok they is no sign of water ingress and i can hear it clicking. I appriciate the help anyway. The ABS is still behaving the same. :?

[Andy T 0]

I've had this problem, turned out to be bent ABS rotors on the front hubs. Dirty Rotors/ abs sensors could also cause it, possibly the rear ones too.

 

If you take a front wheel off, you can check the abs rotor by spinning the hub, distance between rotor & sensor should stay constant.

[paul20v 0]

I've had this problem, turned out to be bent ABS rotors on the front hubs. Dirty Rotors/ abs sensors could also cause it, possibly the rear ones too.

 

If you take a front wheel off, you can check the abs rotor by spinning the hub, distance between rotor & sensor should stay constant.

hi bang on i would say dirty sensor rings it causes the abs sensors to miss read and effectively tell the abs you are having wheelslip as you are pulling up to a stop ,i had it with a 90 quattro once cleaned the abs rings and all was good ,and not the only car its happened to which i have fixed the same way :)

[dr_mat 0]

It can also be caused by borderline ABS sensors. Just cos the light stays off doesn't mean they're not faulty ..

[paul20v 0]

It can also be caused by borderline ABS sensors. Just cos the light stays off doesn't mean they're not faulty ..

get an abs diagnostic , diagnostic can measure abs sensor individual speed readings ,or bring a fault code up

but clean the rings first its free.

[corrado g 0]

Thanks for he replies i will have a go at cleaning the rotors and see if that cures it.

[corrado g 0]

Bit of an update on this and I found the drivers side ABS rotor to be slightly bent so straightened it out, and gave the whole lot a good clean, and its now working.

[Andy T 0]

Bit of an update on this and I found the drivers side ABS rotor to be slightly bent so straightened it out, and gave the whole lot a good clean, and its now working.

 

What did you use to straighten it? Would be interesting to know, when I tried I couldn't find enough room to get in there with any of the tools I had, ended up taking the hub off !

[dr_mat 0]

TBH replacement ABS rotors are very cheap, but you have to have the damn hubs off to do it, pita..

[corrado g 0]

I took off the caliper and disc and put it straight with a pair of pliers. If I had no joy with that then new rotors would be put on. Cheapest method comes first. :lol: