I am not the most experienced but, have you tried a stopping (getting to her sit) her to the whistle or tried to make her sit with voice as shes coming towards you before she loses interest? Think that's what I would try with loads of fuss and rewards when she gets it right, then she might get the idea she has to pay a little more attention.
Ilka used to go towards cars and things quite a bit when we walked down the road when she was younger but shes grown out of it and has lost interest in them and has got used to standing up against the hedges while they pass (narrow country lanes)
Love the photos of Jumble and the one on lm photos.
