Abs problem

Hi people,

my mums octavia has got a issue with the abs system, ill start from the start so you guys know where im at

when it is on a rolling road, the front left wheel jumps out of the road, but if you touch the break pedal it cures this problem, but the abs light used to come on

the car has now had new front discs and pads, hydrolic pipes, new, sensors, new abs module and rebled, the light now stays off, but if you put it back on the rolling road for the end part of the mot, it does it again

trys to jump out of the rolling road, but reapple the foot break and let go, its ok, does anyone have any ideas, or is this normal for a skoda

if you jack the front up and try to turn the wheels without the ignation on, its all ok, but, if you start the engine or swtich on the igination and try to turn the wheels they lock up with a jude

hopefully someone can shed some light

Thanks