Northern California Coast, CA - Cigar

We were travelling along the coast of California going North--this was about 15 years ago, so I can't remember the town we were near. We had a car and van filled with a baseball team from Washington State, and were heading home at 10:00 or so at night(it could have been later). I looked out the driver's window and noticed this oblong object that seemed to be keeping pace with our vehicles. At first I just thought it was an airplane, but the more I watched it, the more I became con- vinced it was not an airplane. Suddenly, it seemed CLOSER, and as the two vehicles went down a small hill on the highway, all our lights, radio, EVERYTHING on the van in the front of us and in our car went out. I looked at the object and it looked closer still and looked to be hovering. We pulled over to the side of the road as quickly and as safely as we could when you have no lights or any guidance, and stopped. My husband got out of the van, and just as he said, "What was THAT?? What is going on??!!", all the lights came back on in our vehicles, and the oblong object had just dissappeared. I wouldn't have believed this if I hadn't seen it with my own eyes. I must tell you that our cars did not stop running, but everything else did--even the heater we had on.