use a long leash when you're out with her, a long line, keep her attached to it, if you turn your head or busy doing something else you can ensure you step on it before you take ur eyes off her.
NOW is the time to work on it with her, have high value treats with you all the time, generally run the other way call her name, never EVER chase her yourself, always have HER chase you.
Make it a FUN and fast game, clearly she loves chase, so use that to make her chase youuuuu and laugh and play and reward when she catches up with you!
Recall recall recall and more recall training
Never use her name or use come for something that's no fun to her (for example I use a command for LEASH ON, so I don't have to call them to me for a boring having to go on leash again, lol)
Sit with her outside near cars, reward her reallllly fast at first once she looks at a car you say GOOD and reward (fast). She looks at it again, you repeat! This will help immensely later once herding instinct with cars reallly kick in... it will get her to redirect to you first when seeing a car, since will then have been conditioned to see them as magic that makes you drop yummy pieces of cheese into her mouth
After a while of doing that I was able to get Toffee to ask me if he could chase something, or I can say WAIT, then sometimes (rarely) I used to be lucky enough to actually let him chase (18 wheeler trucks, in safe fenced area) I use that for birds also.
I was out of my mind for a while because Toffee would NOT stop chasing cars or lunging on leash, ESPECIALLY if he was surprised by one.. NOW I have moved and I live on a super busy road with Oil tanker trucks roaring by my street all day long, we can go for a walk right by it and he doesn't bat an eyelash, or if he does get surprised he looks at me first as if to ask, hey did you see that truck! You owe me a piece of cheese lol
always be diligent it's super scary, but you can help a lot by training for it, too
