ABS light on dash comes on and car is not running right

A failed charging system is the best suspect. With the engine running, measure the battery voltage with an inexpensive digital voltmeter. You must find between 13.75 and 14.75 volts. If it is low, suspect the generator, but there are a couple more tests we should do before you replace it. If the voltage is okay, that only means it is okay to do the second half of the tests, and that requires a professional load tester. In particular, "full-load output current" and ripple" voltage must be tested. One failed internal diode of the six in the generator will reduce output current to exactly one third of maximum, and that is not enough to run the entire electrical system under all conditions.