Alternator/generator/regulator problems of the 1998 Hyundai Accent

Purchased the vehicle in June, 1998. From date of purchase, engine check sensor would come on and stay on for a while. Sometimes the mechanic found a problem and fixed it and turned off the light; sometimes he told me it was a faulty sensor; sometimes he was unable to determine what was causing the light to come on. Latest incident occurred on may 15, 2001, when the engine check light came on once again. The vehicle had just been to the dealership b/c the check engine light was on and they'd replaced the pulse generator. There have been acceleration problems with the vehicle in the past; sometimes the mechanic said that they coincided with the check engine light problem. After 3 years and many visits to the mechanic for the same problem, I'm facing the end of my warranty and the latest explanation for the check engine light problem is that the sensor is "touchy. " ignoring the light in the future is an unaccepteable and unsafe solution, and I don't believe that it is as "touchy" as it is "faulty. ".