NHTSA Complaint #10182780 — 2007 CHEVROLET SILVERADO 1500

2007 CHEVROLET SILVERADO 5.3L V-8 ENGINE WITH ACTIVE FUEL MANAGEMENT AND THROTTLE BY WIRE. VEHICLE WILL NOT IDLE DOWN PROPERLY OR SLOW DOWN PROPERLY OR TIMELY. I BELIEVE 2 POSSIBLE CAUSES, ACTIVE FUEL MANAGEMENT SYSTEM TRYING TO MAINTAIN "SAIL SPEED" IN A FUEL SAVING MODE AND/OR THROTTLE POSITION SENSOR DOES NOT KNOW WHERE THE DRIVERS FOOT IS. VEHICLE PERFORMS LIKE THE CRUISE CONTROL IS ON AT ALL TIMES, WILL ULTIMATELY SLOW DOWN AFTER EXCESSIVE AMOUNT OF TIME. LOW SPEED OPERATION IS ESPECIALLY PROBLEMATIC BRAKES ARE CRITICAL IN CONTROLLING ENGINE SPEED AND OBVIOUSLY VEHICLE SPEED. WITH FOOT OFF ACCELERATOR VEHICLE WILL MAINTAIN 10 MPH SPEED IN PARKING LOT, WILL TRAVEL UP HILL FOR APROX. 30 TO 50 FEET BEFORE BEGINNING TO DECELERATE. THROTTLE RESPONSE IS EXTREMELY DELAYED AND TRANSMISSION SHIFT POINTS ARE CONFUSED AT TIMES. AT TIMES I PLACE VEHICLE IN NEUTRAL GOING DOWN HILL TO GET ENGINE OUT OF SUSTAINED V-4 FUEL SAVING MODE SO I CAN BETTER CONTROL DOWNHILL SPEED. DEALER CONTACTED AND VEHICLE INSPECTED, I WAS INFORMED THAT IS THE WAY THE SYSTEM OPERATES AND CAN NOT BE ADJUSTED. ALSO TOLD THAT CALIFORNIA EMISSIONS STANDARDS PROHIBIT COMPLETE ENGINE IDLE DOWN BECAUSE SUDDEN IDLE DOWN WILL GENERATE UNBURNED FUEL. I WAS TOLD THAT THE MAINTAINED SPEED WAS THE "SAIL SPEED" AND THAT WAS JUST THE WAY IT IS DESIGNED TO OPERATE. VEHICLE PERFORMANCE IS NOT CONFIDENT OR PRECISE, DRIVER MUST BE CONSTANTLY AWARE OF UNINTENTIONAL ACCELERATION VIA SUSTAINED SPEED AND LACK OF DECELERATION WHEN WANTED. *JB