So my friends had I nipped out at lunch for a bite. We came back and parked in the driveway at work to chat. We had all the windows open and the car was off and keys in my purse.

And all of a sudden, there was this giant BANG. Scared the crap out of us!

We all got out and looked underneath, nothing seemed amiss. I timidly started it, and there was no problem. I drove around the parking lot (approx 20km/h) and again, it seemed fine.

What could it have been????