NHTSA Complaint #11180708 — 2012 MERCEDES-BENZ E350

ENGINE. PROBLEM STARTED IN MARCH 2017. 2012 E350 CONV MADE A LOUD GRINDING METAL ON METAL NOISE ON COLD START, BUT WOULD FADE OUT IN A FEW SECONDS. BROUGHT CAR TO DEALER, WHO SAID MECHANICS COULD NOT DUPLICATE PROBLEM. BROUGHT CAR HOME AND CAR CONTINUED TO MAKE GRINDING NOISE. TOOK VIDEO OF NOISE ON COLD START SO I COULD SHOW MY SERVICE ADVISOR. MERCEDES SAID TO REPLACE ENGINE TENSIONERS, TOTAL COST OF REPAIR 1900.00. BROUGHT CAR HOME. CAR CONTINUES TO MAKE GRINDING SOUND ON COLD START. BROUGHT CAR BACK. MECHANICS SUGGESTED CHANGING THE OIL PUMP, TOTAL COST 570.00. BROUGHT CAR HOME, AND CAR CONTINUED TO MAKE GRINDING NOISE ON COLD START. BROUGHT CAR BACK TO DEALER FOR THE THIRD TIME, WHO THEN CALLED MERCEDES FOR ADVICE. SERVICE ADVISOR SAID MERCEDES THINKS THAT THE CAR HAS A CAMSHAFT PROBLEM AND THE COST OF PARTS ALONE WOULD BE OVER 5000.00. MY CAR WAS IN THE SHOP FOR OVER 2 MONTHS AND THERE WAS STILL NO DEFINITIVE ANSWER AS TO WHAT WAS CAUSING THE GRINDING METAL ON METAL NOISE. THIS IS ABSURD AS I HAVE HAD MY CAR SERVICED REGULARLY AND IT IS GARAGED IN GREAT CONDITION. THIS IS OBVIOUSLY AN ENGINEERING/MECHANICAL DEFECT AND SHOULD BE CONSIDERED A LEMON SINCE MERCEDES HAS NOT BEEN ABLE TO FIX OR DIAGNOSE THE PROBLEM IN A TIMELY MANNER. AS OF TODAY, FEB 17, 2019, MY CAR IS STILL MAKING A GRINDING METAL ON METAL NOISE ON BOTH COLD AND WARM START. JUST WONDERING IF ONE DAY MY ENGINE WILL SUDDENLY BLOW UP ON COLD START...