Brake pedal pulsing - Mk4 Golf

[moustache]

I am trying to diagnose a fault with my wife's Mk4 Golf 2.0 GTi, where the brake pedal pulses at low speed only

This is definitely not due to dirty/gritty/unused discs as I have run the car for a while to check this wasn't the case. There isn't anything to suggest why it has occured, in other words no work has been carried out since it started happening.

Any help appreciated, thanks.

[SuperchargedVR6]

Sounds like the ABS is kicking in. Usually caused by defective ABS sensors, hub rings or pedal position sensor (if fitted).

[moustache]

Cool, thanks.

Not sure if I have actually been able to narrow it down via this method but I removed fuse number 9 (ABS fuse) in order to see if the problem persists. Just did a low speed run with it disconnected and it still occurred.

Assuming I had disabled the ABS this way and I still have the symptoms, I am guessing this now points to uneven wear on the disc/pad? I won't say warped discs as I know this is rare and I certainly do not drive this car like a racer!

[SuperchargedVR6]

Rust on the discs?

Another way to disable the ABS is to pull one of the sensor plugs. They're usually on a strut tower at the front, easy to get to.

Had exactly the same issue on my old Corrado and that was caused by a faulty pedal sensor.

[moustache]

SuperchargedVR6 said:

Rust on the discs?

Another way to disable the ABS is to pull one of the sensor plugs. They're usually on a strut tower at the front, easy to get to.

Had exactly the same issue on my old Corrado and that was caused by a faulty pedal sensor.

Thanks for the advice, I will disconnect ABS sensor at the weekend and retest to double check.

I am now starting to suspect contaminated pads/discs as the car spends a fair bit of time not being used (which led to a dead battery).

I shall also charge up my laptop and do a vagcom fault code check too.

Edited by moustache on Thursday 14th January 08:52