Odd car problem...

[Scottastic]

So, my girlfriend and I were driving home from my mother's house (about an hour and a half drive) and the strangest thing happened. The light from the headlights suddenly flashed orange/red for about 2 seconds. I thought I just imagined it, until it happened again about 30 seconds later. My girlfriend asked me if I had noticed it and that confirmed that I was actually seeing something.

We immediately pulled over and I checked under the hood. The oil was fine and the radiator overflow was a tiny bit low, but pretty normal for the car. There was nothing dripping on the ground. I let it sit for another 3-4 minutes and started the car. Looked under the car again and noticed a clear liquid dripping on the ground - one drop every 4 seconds or so. The drip was coming from the exhaust system (I think) fairly close to the middle of the engine block.

We limped the car the rest of the way (10 minutes) and I noticed that there was a "hum" that wasn't there before, but I might be paranoid. Don't know much about cars, so I was wondering what you guys think might be the problem. If it helps it's an '86 VW Jetta Automatic.