Etymology Puzzler

The Puzzler has returned! Now, this was sent to us. And we're not going to give the name of the person who sent in the puzzler just yet. Why? Because all their friends will try to call them up and try to get the answer! So we'll tell you next week!

Okay, here we go. Yeah. So the submitter says, "Everybody listening to Car Talk knows all about jalopies" (I.e. broken down cars with too many miles and like 63 Dodge Dartres.) "But what is a jalopy and why is it called a jalopy?"

Just a humble little question. In other words, what is the derivation of that expression "jalopy"?