Engine control system for intake valve opening timing during cold start

1 . An engine control system, comprising:

an electric heater configured to increase a temperature of intake air within an engine; and

at least one controller in communication with the engine and the electric heater, the at least one controller being configured to:

detect a starting condition of the engine;

monitor a first temperature value associated with the engine during the starting condition of the engine;

compare the first temperature value to a first temperature threshold;

initiate, in response to the first temperature value being below the first temperature threshold, at least one of delaying opening of an intake valve by an intake valve delay system or turning on the electric heater;

detect a second temperature value associated with the engine subsequent to the first temperature value;

compare the second temperature value to a second temperature threshold, greater than the first temperature threshold; and

responsive to the second temperature value exceeding the second temperature threshold, disengage one of the intake valve delay system or the electric heater while maintaining the engagement of the other of the intake valve delay system or the electric heater.

2 . The engine control system of claim 1 , wherein the at least one controller is further configured to:

initiate, in response to the first temperature value being below the first temperature threshold, delaying opening of the intake valve by an intake valve delay system and turning on the electric heater;

monitor the first temperature value subsequent to initiating the at least one of delaying opening of the intake valve or turning on the electric heater; and

initiate, in response to the first temperature value being above the first temperature threshold, at least one of turning off the electric heater or cancelling the delay of the opening of the intake valve.

3 . The engine control system of claim 1 , wherein the first temperature value is at least one of an engine temperature of the engine, an intake air temperature, a coolant temperature, an oil temperature, or an exhaust temperature of exhaust gases from the engine.

4 . The engine control system of claim 1 , wherein the engine is a multi-fuel engine.

5 . The engine control system of claim 1 , wherein the engine has a compression ratio less than 15:1.

6 . The engine control system of claim 1 , wherein the engine is a mono-fuel engine operating on a low cetane number fuel, wherein the low cetane number fuel is at least one of methanol or ethanol.

7 . The engine control system of claim 1 , wherein the intake valve is part of a lost motion system.

8 . The engine control system of claim 1 , wherein the intake valve is part of a variable valve timing system.

9 . The engine control system of claim 1 , wherein the intake valve is part of a variable valve lifting system.

10 . An engine comprising:

an intake valve delay system;

an electric heater configured to increase a temperature of intake air within the engine; and

at least one controller in communication with the engine and the electric heater, the at least one controller being configured to:

monitor a first value of one or more parameters regarding operation of the engine;

determine that the engine is expected to fail to start or be slow to start based on the first values of the one or more parameters;

initiate, in response to determining that the engine is expected to fail to start or be slow to start, at least one of delaying opening of an intake valve by the intake valve delay system or turning on the electric heater;

detect a temperature value of the one or more parameters associated with the engine subsequent to the first values;

compare the temperature value to a temperature threshold; and

responsive to the temperature value exceeding the temperature threshold, disengage one of the intake valve delay system or the electric heater while maintaining the engagement of the other of the intake valve delay system or the electric heater.

11 . The engine of claim 10 , further comprising an aftertreatment system in communication with the controller, the controller being configured to:

initiate a regeneration event in the aftertreatment system based on an indication that the aftertreatment system requires regeneration;

detect a load condition in the engine corresponding to a temperature of exhaust gases of the engine being less than a target temperature for the regeneration event of the aftertreatment system; and

initiate the delayed opening of the intake valve or the turning on of the electric heater, based on the load condition.

12 . The engine of claim 10 , wherein the intake valve opening is delayed on only a subset of a plurality of intake valves comprising the intake valve.

13 . The engine of claim 10 , wherein the at least one controller is further configured to:

monitor the engine to determine an exhaust temperature value subsequent to initiating the at least one of delaying opening of the intake valve or turning on the electric heater;

compare the exhaust temperature value to a threshold; and

initiate, in response to the exhaust temperature value being above the threshold, a second action, wherein the second action is at least one of turning off the electric heater or not delaying the opening of the intake valve.

14 . The engine of claim 10 , wherein the at least one controller is configured to determine that the engine is expected to fail to start based on determining that the first values of the one or more parameters do not satisfy one or more thresholds relating to performance of the engine.

15 . The engine of claim 10 , wherein the at least one controller is configured to determine that an emissions output of the engine is expected to exceed an emissions output threshold based on the temperature and a fuel composition comprising multiple fuels.

16 . A method of emissions reduction for cold start engine operation, the method comprising:

detecting a first temperature value associated with an engine at a starting of the engine;

comparing the first temperature value to a first temperature threshold;

responsive to the first temperature threshold exceeding the first temperature value:

engaging an intake valve delay system to delay opening of an intake valve; and

engaging an electric heater;

detecting a second temperature value associated with the engine subsequent to the first temperature value;

comparing the second temperature value to a second temperature threshold, greater than the first temperature threshold; and

responsive to the second temperature value exceeding the second temperature threshold, disengaging one of the intake valve delay system or the electric heater while maintaining the engagement of the other of the intake valve delay system or the electric heater.

17 . The method of claim 16 , further comprising:

engaging the electric heater responsive to a comparison of a battery state of charge (SoC) to a SoC threshold.

18 . The method of claim 16 , further comprising:

determining, based on a fuel composition of a multi-fuel vehicle, the first temperature threshold.

19 . The method of claim 16 , wherein the engine has a compression ratio of less than 15:1.

20 . The method of claim 18 , further comprising:

detecting a third temperature value associated with the engine subsequent to the second temperature value;

comparing the third temperature value to a third temperature threshold, greater than the second temperature threshold; and

responsive to the third temperature value exceeding the third temperature threshold, disengaging the other of the intake valve delay system or the electric heater.