NHTSA Complaint #10484970 — 2013 BMW X5

VEHICLE DEVELOPED SIGNIFICANTLY REDUCED FUEL MILEAGE AFTER THE FIRST 500 MILES. IN TOWN RANGE DROPPED BY 40% TO 7.8 MPG OVER THE SAME ROUTE, INDEPENDENT OF GASOLINE SOURCE OR GRADE. EXHAUST GASES ARE VERY HOT AND EXHIBIT A PRONOUNCED SULFURIC, GUNPOWDER LIKE SMELL. ELECTRICAL FANS CONSTANTLY ON DURING CITY DRIVING ATTEMPTING TO COOL THE ENGINE. EXCESSIVE CARBON BUILD UP ON EXHAUST COMPONENTS. ENGINE EXHIBITING RICH RUNNING CONDITION. A PERSISTENT MECHANICAL ENGINE WHINE DEVELOPED EMANATING FROM THE OIL PUMP, POSSIBLY THE ALTERNATOR AREA OF THE ENGINE COMPARTMENT, PEAKING AT 1700-1900 RPM UNDER LOAD. AT 1,200 MILES, THE 8 SPEED AUTOMATIC TRANSMISSION DEVELOPED ERRATIC SHIFT BEHAVIOR BETWEEN 1ST-3RD GEARS. AT FAIRLY CONSTANT SPEED, THE TRANSMISSION IS SHIFTING BETWEEN 1ST AND SECOND GEAR, ALTERNATING UP SHIFTING AND DOWNSHIFTING WITHOUT ESTABLISHING PROPER GEAR. COMING TO A STOP, VEHICLE SURGES REVOLUTIONS BY UP TO 500 RPM ON THE 3-2 DOWNSHIFT AND UP TO 800 RPM ON THE 2-1 DOWNSHIFT, CAUSING A SUDDEN AND ABRUPT HALT, ENGINE BRAKING EFFECT. BEHAVIOR IS MOST PRONOUNCED IN STANDARD D TRANSMISSION MODE, MINIMIZED IN DS MODE AND COMPLETELY ABSENT IN MANUAL MODE WITH AUTOMATIC DOWNSHIFT. AT 2,200 MILES, GUNPOWDER LIKE EXHAUST GAS SMELL MORE PRONOUNCED AND EVIDENT WHILE AVERAGE FUEL MILEAGE DROPPED TO 6.4 MPG OVER THE SAME COURSE. TRANSMISSION EXPERIENCED TWO INCIDENTS OF FAILING TO UP SHIFT INTO SECOND GEAR FOLLOWED BY A MECHANICAL CLUNK AND SHARP JOLT AFTER FINALLY GETTING IN GEAR. VEHICLE DOES NOT EXHIBIT ANY STORED OR ACTIVE FAULT CODES WITHIN THE ON-BOARD DIAGNOSTICS. *TR