NHTSA Complaint #10206727 — 2007 MINI COOPER US

(1) A DEISE-LIKE RATTLING NOISE, NOT IN TIME WITH THE ENGINE, COMING FROM UNDER THE HOOD ON START-UP. THE NOISE WOULD EVENTUALLY GO AWAY AS THE ENGINE WARMED UP. AS TIME PROGRESSED, THE NOISE GREW LOUDER AND TOOK LONGER TO SUBSIDE. VEHICLE WAS EVENTUALLY TURNED OVER TO THE DEALER FOR EVALUATION. (2) THE NOISE WAS DETERMINED TO BE A FAILURE OF THE OIL-FED CAM CHAIN TENSIONER. THE PISTON WAS DETERMINED TO BE STARVED OF OIL, CAUSING THE CAM CHAIN TO CREATE A RATTLING NOISE INCREASING IN VOLUME AND DURATION. (3) PARTS WERE ORDERED TO FIX THE CAM CHAIN TENSIONER AND THE PISTON AND TENSIONER WERE REPLACED. THERE IS STILL SOME RATTLING ON START-UP, BUT THE NOISE HAS SIGNIFICANTLY DIMINISHED. SEVERAL OTHER OWNERS ONLINE HAVE REPORTED SIMILAR ISSUES AND IT APPEARS THE REPLACEMENT OF THE CAM CHAIN TENSIONER IS A TEMPORARY FIX (WITH THE NOISE RETURNING SOME WEEKS LATER). FAILURE OF THE CAM CHAIN TENSIONER WILL LEAD TO ADDITIONAL WEAR ON THE CAM CHAIN EVENTUALLY DAMAGE TO THE ENGINE CASE, CAMS AND VALVES THEMSELVES. A CATASTROPHIC ENGINE FAILURE WILL OCCUR IF THIS ISSUE IS NOT ADDRESSED. *TR