For a native English speaker, the verb ‘borrow’ fits perfectly into the original sentence.
Yes, though you have to be careful with ‘took’ as it can imply that the intention was not to return it.
Yes, since ‘borrow’ means to get or to use something on the understanding that it will be returned, your sentence is more intelligible, polite and suitable. Further, it faintly implies that the person concerned is not a total stranger to the car owner (probably a casual acquaintance). Otherwise his reaction would have been different.
Now, suppose you leave your car with its key and go to buy something at a shop nearby. On return you find someone parking the car back at the same place after using it. I don’t think you will then say: You could ask me before you borrow my car, for, in this context, it is not borrowing. In fact, taking away anything without the owner’s consent is tantamount to stealing, and not borrowing.
This is becoming quite nonsensical. You should not have to make up scenario after scenario about this. The simple fact is that if you say to someone:
You should at least have asked me before you took my car.
this is clearly someone you know or your reaction would have been very different. Although I have advised of the need to be careful using ‘took’ in my message above, I really don’t think there is a need to be so dogged about it.
Fathima, you have posted this question. Unfortunately, the discussion has led to sensible and senseless arguments/observations. I would like to know (sincerely) the context you have in mind of this sentence or the context in which you actually used this statement. You may send me a PM if you think that it will not be useful to others. Thanks.