05 Passat ABS judder?

[Autogasm]

Hi all, my friends 05 plate passat 1.9 tdi 110 has a strange braking fault. As you come to a halt, not braking particularly hard at all, the brake pedal pulsates as though the ABS is operating, even though the wheels are not locking.

The car was recenlty serviced, the brakes are good, the tyres are recent on the front (Did it before the tyre change too), and it does this on perfectly dry roads! Any ideas?

[VAG1]

could be warped discs?

[javalin]

Is it just before you stop? It could be the shocks - good contact with the road is obviously essential and affects the loading on the wheel.

James

[Autogasm]

Hi there, Thanks for the suggestions but definitely not discs or shocks. It literally feels as though the ABS kicks in though the road conditions are dry. Slowing gently from just 5mph can cause it to occour. Infact seems worse when braking gently?

[AdrianR]

ABS sensors in the hubs are either misaligned or faulty. Last time this question was asked it turned out the car had had brake work recently - has yours?

[Autogasm]

Thanks for that, sounds like a possibility. Haven't had any work done but you never know! I'll get it checked. Thanks again

[Dr G]

Sticking caliper is a possibility also, worth getting them ooked at and cleaned (not expensive if it's just dirty).

[Thirsty33]

AdrianR said:

ABS sensors in the hubs are either misaligned or faulty. Last time this question was asked it turned out the car had had brake work recently - has yours?

Yes this is most likely - happended to me after I had shocks replaced. Aparently the sensors are magnetic and can pick up bits of rust. When this happens they don't work properly. If you've not had work around that area, they might just be faulty, but worth finding them, taking them off for a clean and replacing.

[dougc]

Just thought I'd update this thread. My Dad asked for help a week or so ago when his ABS started cutting in at very low speed for no good reason. I did a search and found this.

He had a CV boot replaced on the drivers side front and the next day, the juddering problem started. Couldn't drive 2 miles without it happening. He took the car back to the VW 'specialist'. They plugged in the diagnostic machine and diagnosed a faulty ABS controller at (conveniently) a large premium to supply and fit to fix the problem.

He phoned me and I found this thread.

Back the car went and the ABS sensor was inspected, cleaned and re-aligned.

Two days and 50 miles later and the problem has gone.

Thanks PH

[Tame Technician]

False abs activations are nearly always down to dirty or mis-positioned ABS sensor.

Very occasionally its a faulty sensor or the wire to the sensor has an intermittent break.