I drive a stock '99 Cougar with the 2.5 V6 and automatic transmission with about 52,700 miles on the odometer right now. I bought this car about 4,000 miles ago, and at least for a good part of the time I've owned it, I've noticed that when driving on the highway, maybe every 30-90 seconds, the engine seems to almost "skip a beat." It's nothing major and doesn't seem like a misfire, but it's noticeable nonetheless. It almost sounds like that for a tiny fraction of a second, I've let way off the accelerator or something, when in fact I haven't. This only occurs at highway speeds, and it doesn't seem to matter where the tach needle is sitting, how fast I'm cruising (55+ MPH), what grade of gas is in the tank, or how full or empty the gas tank is. There is no check engine light, and the only code I've gotten out of it is 9318, the all-too-common low voltage thing. Fuel economy hasn't been sacrificed. Any suggestions?