NHTSA Complaint #11436870 — 2012 KIA OPTIMA

While driving approximately 55 mph, the vehicle produced a grinding noise then lurched a few times every couple of minutes and then the engine shut down. Luckily I was able to safely coast to a stop while going downhill and stop the vehicle at the side of the road. Turned the engine off, waited one minute, then pushed ignition button. Hybrid system started but engine did not. Shifted to Drive, pressed accelerator, but vehicle would not proceed. Turned everything off and waited five minutes. Pushed ignition button and hybrid system and engine started and shifted to drive. Vehicle would drive at underpowered speed and was able to drive 2 miles home at 35 mph. As I drove into driveway, the engine shutdown again. This occurred just a few hours ago, so it has not been serviced by anyone.