Why rough Idling after low oil pressure light came on

Hello, How long has the vehicle been driven with the low oil pressure light on? Is it still on? Was it low on oil? Is the engine making noise while running (click, clack, rattle, tap, thump, knock, whirring, squealing)? EDIT*** I just saw you had another post up with a more in depth description. Your engine will likely require rebuilding or replacing. When an engine is low on oil pressure, metal surfaces that normally rotate with an oil barrier will begin rotating on metal. When this causes the vehicle to stop running, it is most likely due to internal damage. There is a possibility that the engine can be salvaged, but 15 miles (15-20 minutes) without oil pressure is enough to call for replacement.