Brake Pedal Judder ?constant Abs

[SEEMO]

Hi,I have not driven my vehicle(RS2 MTM) for a month.Since driving it again the brake pedal has a constant judder regardles of whether the brakes are applied or not.It is as if the ABS is is being activated constantly.The braking does not seem to be affected.
The brake warning light has also come on.Any ideas/ suggestions would be much appreciated.
Kind regards
Seemo

[waad_uk]

First thought for me would be a duff abs sensor. If it thinks the wheel is not rotating (i.e skidding) when the pedal is pushed it will pulse the brakes

[Acidburn]

I've got something like this atm as i've got a rear wheel bearing that needs changing so I think its worn the abs sensor out as well so i've got to change this.

[Cullam3n]

Can almost guarentee this is a hydraulic servo issue if its not an ABS sensor (if it does it stationery).

[SEEMO]

Thanks for the advice I will have these checked and let you know .
Cheers
Seemo

[Error404]

loads of servo failures ATM!! Whats going on

[Cullam3n]

Also easy way to rule out ABS is see if the pulsing changes with the revs, if it does definite servo issue

[Acidburn]

mine does it when i'm slowing down to about 5-10miles an hour, still think its an issue with the passenger rear abs sensor due to my wheel bearing.

[Knight Rider S4]

vag.com will tell you if you have issues with sensors

[Acidburn]

cheers thats another reason for me to get better and have a go with it, got all the bits just been ill since.

[popdemonic]

If you rev up the engine and the symthom is lesser.I'd go for the new Accumulator.
the brake servo is probably your cause.butIt's rarely die.I had this issue year ago.

[popdemonic]

to clear up this,the bomb or accumulator will act like the reserved pressure from the PS Pump.when the Bomb is died (the check valve ,relief valve stuck)or the gas is discharged so the pressure will not be hold up.So the brake assisted will use the pressure directly from the PS pump.when you rev up the engine.the brake pedal
'd feel softer and no any pulsating via pedal.The PS pump cycling cause the pedal pulsated.

[dan_b]

Defintely check the bomb (accumulator). There are threads about how you test the bomb on the forum, the forum's best friend The Search should help as a start...