Epc light and noise after start up

One day I was sitting in line for the car wash idling, when my car dies, first time its happened I just bought this car. So I start it back up and it works fine except my epc light stays on so I drive until I get home and then I went to start it up the nextday and it starts fine but I hear a noise it sounds like something is either not closing fast enough or its closing you fast, as if air is escaping a valve or soemthing my epc light stays on until the noise dissapates which lasts about 1-2 seconds different evetrytime. The car runs normally and has no other problems, I dont even know what this could be.