Brake pedal judder when lightly depressing pedal (as if ABS kicking in) Pads and discs are fine. Sister had same problem with her VW Passat and said that a mechanic cleaned off ABS detectors.

It might be this as it occured after I used a High pressure Diesel Karcher washer - anyone else had this problem and how did you solve it?

Exciter rings on the front axles are probably cracked. Cause intermittent ABS function. Must replace axles. expensive.

Yeap

Jacked up and took off the wheels - was a broken exciter ring as you said - new CV required - £299 drivers side

thanks for the info