LOL.....yes, but.....
I started out a year ago with a spring and a dream of a knife made fast and easy...
But what happens is that one thing leads to another....as you seek to make things better and easyer, you add more and more tools to your shop....next thing I knew I had a forge burning and my arms were sore from hitting 1 and 1/2 inch steel shafts into knives...
"I should get a power hammer"
and so my tool collection goes on?
so, my answer is yes, you can use steel right off the car to make a blade out of, however it would be easyer to work if you heated the steel and annealed it so it was softer ....and thats how it all starts....LOL