Patent ID: 7661412

Claim:
A method of controlling the startup of an indirect injection internal combustion engine ( 28 ), said indirect injection internal combustion engine comprising: a plurality of cylinders ( 12 ), a piston ( 14 ) in each of said cylinders sliding between a bottom dead center ( 30 ) and a top dead center ( 32 ), a crankshaft whose rotational movement is linked with the sliding movement of each of the pistons ( 14 ), an inlet valve ( 16 ) and an exhaust valve ( 18 ) moving between an open position and a closed position, and being associated with each of the cylinders ( 12 ), an inlet manifold ( 20 ) associated with said each of the cylinders ( 12 ) and connected by an intermediary of said inlet valve ( 16 ) associated with said each of the cylinders, and an injector ( 26 ) associated with said each of the cylinders ( 12 ) for injecting fuel into the inlet manifold associated with said each of the cylinders, ignition means ( 24 ) associated with said each of the cylinders ( 12 ) for igniting the fuel contained in said each of the cylinders ( 12 ), a crankshaft position sensor ( 2 ) comprising a fixed part ( 4 ) and a target ( 6 ) linked with the crankshaft, said target comprising a reference index ( 10 ) detectable by the fixed part ( 4 ), said method comprising the following steps: commanding starting of the rotation of the crankshaft from a starting position (P 1 , P 2 , P 3 , P 4 ) of the engine, detecting the rotation of the crankshaft, selecting a group of cylinders and for each of the selected group of cylinders, detecting the reference index ( 10 ) less than a half-turn of the crankshaft before the piston ( 14 ) associated with it reaches the top dead center ( 32 ), commanding the injectors ( 26 ) associated with the selected group of cylinders such that the injectors finish injecting fuel into the inlet manifolds ( 20 ) associated with the selected group of cylinders before the crankshaft has turned through 75 degrees with respect to the starting position (P 1 , P 2 , P 3 , P 4 ) of the engine, such that at least one of the inlet valves ( 16 ) associated with the selected group of cylinders changes ( 16 b ) from the open position to the closed position, detecting the reference index ( 10 ), commanding the ignition means ( 24 ) to ignite said each of the selected cylinders at a time determined as a function of the detecting of the reference index ( 10 ) and substantially corresponding to an arrival at the top dead center ( 32 ) of the piston ( 14 ) associated with igniting said each of the selected cylinders, wherein said method is free of any use of a camshaft position sensor.