Engine control systems and methods for starting an engine

An engine system for a vehicle, comprising:

• an engine comprising a crankshaft, a plurality of combustion chambers, a plurality of pistons coupled to the crankshaft and respectively corresponding to the plurality of combustion chambers, and, for each combustion chamber of the plurality of combustion chambers, an intake valve and an exhaust valve;
• and
• an engine controller, operatively connected to the engine and comprising:
• at least one processor;
• and
• a memory, operatively connected to the at least one processor and storing instructions that, when executed by the at least one processor, cause the engine system to perform a method, the method comprising transmitting, by the at least one processor and in response to receiving an engine start signal, one or more engine control signals that, when received by the engine:
• cause the crankshaft to begin to rotate and to rotate through a first plurality of rotations,
• cause, for each combustion chamber of a first set of combustion chambers of the plurality of combustion chambers, the exhaust valve of the combustion chamber to remain in an open position while the crankshaft rotates through the first plurality of rotations and prior to fuel being injected into the combustion chamber, and
• cause, for each combustion chamber of a second set of combustion chambers of the plurality of combustion chambers, the exhaust valve of the combustion chamber to open and close while the crankshaft rotates through the first plurality of rotations and prior to fuel being injected into the combustion chamber.