Methods for starting a multi-cylinder internal combustion engine
A method is provided for starting an internal combustion engine having a plurality of cylinders, each cylinder having at least one inlet valve and one exhaust valve. In accordance with one embodiment the method includes the steps of opening an inlet valve of any cylinder that would otherwise undergo a wasted power stroke and opening an exhaust valve of any cylinder that would otherwise undergo a wasted compression stroke.
1. A method for starting an internal combustion engine comprising a plurality of cylinders, each cylinder having at least one inlet valve and one exhaust valve, the method comprising the steps of:
providing spark to a first cylinder undergoing a power stroke;
opening an inlet valve of the first cylinder undergoing the power stroke; and
opening an exhaust valve of a second cylinder undergoing a compression stroke.
2. The method of claim 1 wherein the step of opening the inlet valve comprises the step of opening the inlet valve independently of engine timing.
3. The method of claim 1 further comprising the step of inhibiting fueling of the first cylinder when the inlet valve is opened.
4. The method of claim 1 wherein the steps of opening the inlet valve and opening the exhaust valve are independent of engine timing.
5. The method of claim 4 wherein the steps of opening the inlet valve and opening the exhaust valve comprise the steps of opening the inlet valve and opening the exhaust valve electro-hydraulically or electromechanically.
6. The method of claim 4 wherein the steps of opening the inlet valve and opening the exhaust valve comprise the steps of opening the inlet valve and opening the exhaust valve in response to an engine management system.
7. The method of claim 6 further comprising the step of inhibiting fueling of any cylinder undergoing a power stroke in response to the engine management system.
8. A method for starting an internal combustion engine having a plurality of cylinders, each of the cylinders having an inlet valve and an exhaust valve, the method comprising the steps of:
providing spark to a first cylinder undergoing a power stroke;
opening an inlet valve of the first and a second cylinder undergoing the power stroke and an intake stroke, respectively; and
opening an exhaust valve of a third and a fourth cylinder undergoing a compression and an exhaust stroke, respectively.
9. The method of claim 8 further comprising the step of inhibiting the injection of fuel during the step of opening the inlet valve of the first and the second cylinder.
10. The method of claim 8 wherein the steps of opening the inlet valve of the first and the second cylinder and opening the exhaust valve of the third and the fourth cylinder are continued until the internal combustion engine reaches a predetermined rotational speed.
11. The method of claim 10 further comprising the step of inhibiting the injection of fuel during the step of opening the inlet valve of the first and the second cylinder.
12. The method of claim 11 wherein the step of inhibiting is terminated when the internal combustion engine reaches the predetermined rotational speed.
13. The method of claim 12 further comprising the step of terminating the step of opening of the inlet valve of the first cylinder undergoing a power stroke after fuel has been injected into the cylinder on an intake stroke.
14. The method of claim 13 further comprising the step of terminating the step of opening the exhaust valve of the fourth cylinder undergoing the exhaust stroke after fuel has been injected into the cylinder on an intake stroke.
15. An engine system comprising:
an internal combustion engine having a plurality of cylinders including a first and a second cylinder;
a spark plug associated with the first cylinder and that generates a spark to the first cylinder during a power stroke;
an inlet valve associated with the first cylinder;
an exhaust valve associated with the second cylinder; and
an engine management system that opens the inlet valve of the first cylinder performing a power stroke and opens the exhaust valve of the second cylinder undergoing a compression stroke.
16. The engine system of claim 15 wherein the engine management system further inhibits fuel delivery to the engine during opening of the inlet valve.