Any advantage to kneeding down pizza dough 3 times I found though experimentation that while my pizza dough recipe said to only knead the pizza dough once then let it rise,
that the dough came out better if I punched it down, kneaded it, then let it rise a second time, like for bread.

Normally I don't have time for this.
I have some spare time, as I got the dough on its first rise around breakfast breakfast.
Punched it down around lunch, 
and now it has risen again, and would have time to rise again. (Assuming the yeast still functions.)
Or would this be bad,
should I just leave it in my car (where it has been rising) til I prep it for dinner?
Maybe I should put in into the fridge?
The series of folds you're doing serve to degas the dough so that it can ferment longer (thus developing more flavor), and to help strengthen the gluten. A third fold wouldn't hurt most doughs, but in the case of a pizza dough it could make it too tight to be easily workable. I would suggest spacing out the other two folds longer in the future. If your dough looks like it will collapse if it rises any more, punch it down and fold it but  be sure to give it a long time to relax before using it. 

If you just punched it down, you could transfer it to your fridge at this point to slow it down. Just give it time to warm up again before using it.