2015 INFINITI QX50 Engine Problems

THE CAR STARTED NORMALLY AND AFTER DRIVING ABOUT A QUARTER OF A MILE I WAS SUDDENLY COASTING WITHOUT POWER. THE ENGINE JUST QUIT. WITHOUT POWER STEERING AND BRAKES I WAS STILL ABLE TO GUIDE IT TO THE CURB AND COME TO A SAFE STOP. WHAT I ATTEMPTED TO RESTART THE CAR IT ACTED AS IF THE BATTERY DIDN'T HAVE ENOUGH POWER TO TURN OVER THE ENGINE, ALTHOUGH LIGHTS, HORN AND RADIO STILL WORKED FINE. THE CAR WAS TOWED TO THE DEALER WHERE I BOUGHT IT AND AFTER WEEK OF UNSUCCESSFUL TROUBLESHOOTING THE INFINITI REPS GOT INVOLVED. WHEN THE OIL PAN WAS REMOVED THEY FOUND NUMEROUS PIECES OF METAL OF VARYING SIZES AS IF SOMETHING IN THE ENGINE HAD DISINTEGRATED. IF THEY KNOW WHAT CAUSED IT THEY HAVEN;T TOLD ME, AND I SINCE I HAD LEASED IT JUST TWO WEEKS PRIOR I'VE ASKED FOR A NEW VEHICLE RATHER THAN TO HAVE...