Car stalls without warning. Car is able to cruise and brake until I can pull off to the side of the road. Car will restart after turning it off. Speed, time, duration of the drive ds not matter. It happened at 40 MPH, 60 MPH, 80 MPH. It happens 5 minutes into a drive or 20 minutes. Took it to the mechanic multiple times, codes do not pop up. Engine light ds not come on. Mechanic is unable to find the problem.