2014 Audi S4

MY 2014 AUDI S4 HAS A EPC LIGHT THAT KEEPS TURNING ON WHILE DRIVING THAT CAR. THE EPC LIGHT WILL PUT THE CAR INTO LIMP MODE AND WILL HAVE A ROUGH IDLE AND CAN BARLEY DRIVE. WHEN THAT LIGHT TURNS ON YOU HAVE TO PULL OVER IMMEDIATELY AND RESTART THE CAR TO CONTINUE DRIVING AND IS A COMPLETE SAFETY HAZARD BECAUSE IT WILL HAPPEN WHEN YOU ARE ON THE FREEWAY. THE LIGHT MAINLY TURNS ON WHEN YOU ARE TRYING TO GET UP TO SPEEDS OF THE FLOW OF TRAFFIC. I HAVE TAKEN IT TO THE DEALER MANY TIMES TO GET THIS ISSUE RESOLVED AND THEY KEEP SAYING THERE IS NO ISSUE WITH THE CAR WHAT'S SO EVER. I DECIDED TO TRY TO FIGURE OUT WHAT WAS WRONG WITH THE CAR MYSELF BECAUSE THE DEALER WAS NO HELP. WHEN I LOOK IT UP HUNDREDS OF FORUMS SHOW UP TALKING ABOUT IT AND NO ONE CAN FIGURE OUT WHAT IS GOING ON WITH THE CAR AND EVERYONE IS HAVING THE SAME ISSUE AND HOW THE DEALER IS NO HELP AT ALL. ONE PERSON SAID THEY TOOK IT TO THE DEALER AND THERE WAS A FAULTY WIRE ON THE ECU. I THINK ITS THE ECU FAILING AND DOESN'T KNOW WHAT TO DO.

WHILE TRAVELING AT 75MPH, UPHILL, IN 100F WEATHER THE FUEL LOW PRESSURE FUEL SYSTEM DEVELOPED A VAPOR BUBBLE THAT STALLED THE LOW PRESSURE FUEL PUMP AND STARVED THE MOTOR FOR FUEL. THE CAR STALLED ON THE FREEWAY AND WOULD INTERMITTENTLY RESTART UNTIL THE LOW PRESSURE FUEL PUMP FAILED. THE REPAIR REQUIRED ADDITIONAL VALVES AND HOSES HE ADDED TO THE LOW PRESSURE FUEL SYSTEM TO COMPENSATE FOR THE POOR VAPOR MANAGEMENT DESIGN. THE CAR HAD TO BE TOWED TO A DEALERSHIP WHERE THE APPROPRIATE FIX AND TSB WAS EXECUTED. TOTAL COST WAS ~$2200, $715 OF THAT TOTAL COST WERE THE NEW VALVES AND HOSES THAT SHOULD HAVE BEEN PART OF THE INITIAL DESIGN.