A secondary fuel injection system determines (precisely) a maximum amount of secondary fuel that can be injected into a cylinder during a cycle based upon the rotational speed (RPM) of the engine. A primary fuel injection pulse width of the prior cycle and is used to determine how much heat energy was requested by an engine control module based upon the duration of the injection pulse. Secondary fuel is injected into the intake port of the cylinder after the exhaust valve closes in an amount that is calculated based upon the maximum that can be injected during the allowed calculated time of crankshaft rotation and the amount of heat energy requested in the prior cycle and to include the amount of primary fuel that is then injected into the cylinder is being reduced based upon the amount of heat energy provided by the secondary fuel that was previously injected.

A secondary fuel injection system determines (precisely) a maximum amount of secondary fuel that can be injected into a cylinder during a cycle based upon the rotational speed (RPM) of the engine. A primary fuel injection pulse width of the prior cycle and is used to determine how much heat energy was requested by an engine control module based upon the duration of the injection pulse. Secondary fuel is injected into the intake port of the cylinder after the exhaust valve closes in an amount that is calculated based upon the maximum that can be injected during the allowed calculated time of crankshaft rotation and the amount of heat energy requested in the prior cycle and to include the amount of primary fuel that is then injected into the cylinder is being reduced based upon the amount of heat energy provided by the secondary fuel that was previously injected.

A system for reclaiming fuel from a vehicle fleet is comprised of a trailer capable of defueling multiple vehicles simultaneously that operates in conjunction with a remote computing device. The remote computing device communicates bi-directionally with an on-board computing device located in a combustion engine vehicle, where the on-board computing device is directed by the remote computing device to cause the vehicle's fuel pump to operate without starting the vehicle's engine. The remote computing device also queries for and receives data about the vehicle from the on-board computing device, such as the Vehicle Identification Number, diagnostic information about the vehicle, and/or data about how the vehicle is being driven and transmits such data to at least one second computing device in communication with the remote computing device.

A system for reclaiming fuel from a vehicle fleet is comprised of a trailer capable of defueling multiple vehicles simultaneously that operates in conjunction with a remote computing device. The remote computing device communicates bi-directionally with an on-board computing device located in a combustion engine vehicle, where the on-board computing device is directed by the remote computing device to cause the vehicle's fuel pump to operate without starting the vehicle's engine. The remote computing device also queries for and receives data about the vehicle from the on-board computing device, such as the Vehicle Identification Number, diagnostic information about the vehicle, and/or data about how the vehicle is being driven and transmits such data to at least one second computing device in communication with the remote computing device.

A method for operating an engine system 200 comprising an engine 208 configured to consume a fuel, having at least a two flowmeters 214, 216, is provided. The method includes the step of operating an engine 208 disposed between a supply flowmeter 214 of the at least two flowmeters and a return flowmeter 216 of the at least two flowmeters. A first fuel density in the supply flowmeter 214 and a second fuel density in the return flowmeter 216 are measured. The fuel density measurements 317 between the supply flowmeter 214 and return flowmeter 216 are compared and a differential density measurement value, Δρ 319, based on a difference in the second fuel density and the first fuel density is determined. The Δρ 319 is compared to a range of theoretical differential fuel density values, Δρ.sub.t, and potential fuel contamination is indicated if the Δρ lies outside a range of Δρ.sub.t values by a predetermined threshold.

A method for operating an engine system 200 comprising an engine 208 configured to consume a fuel, having at least a two flowmeters 214, 216, is provided. The method includes the step of operating an engine 208 disposed between a supply flowmeter 214 of the at least two flowmeters and a return flowmeter 216 of the at least two flowmeters. A first fuel density in the supply flowmeter 214 and a second fuel density in the return flowmeter 216 are measured. The fuel density measurements 317 between the supply flowmeter 214 and return flowmeter 216 are compared and a differential density measurement value, Δρ 319, based on a difference in the second fuel density and the first fuel density is determined. The Δρ 319 is compared to a range of theoretical differential fuel density values, Δρ.sub.t, and potential fuel contamination is indicated if the Δρ lies outside a range of Δρ.sub.t values by a predetermined threshold.

A system includes an electronic fuel injection system of an engine, the electronic fuel injection system including an electronic governor control unit for controlling various functions of the engine.

A system includes an electronic fuel injection system of an engine, the electronic fuel injection system including an electronic governor control unit for controlling various functions of the engine.

A method is disclosed for controlling an internal combustion engine having a first adjustable camshaft for the actuating of first valve elements of the internal combustion engine. An effect of an actuation at least of a first valve element by the first camshaft on this valve element is detected. An actual position of the first camshaft and/or of a crankshaft driving the latter is detected on the basis of this detecting of the effect. An adjustment of the first camshaft is calibrated on the basis of a first deviation between this detected actual position and a predetermined required position.

A method is disclosed for controlling an internal combustion engine having a first adjustable camshaft for the actuating of first valve elements of the internal combustion engine. An effect of an actuation at least of a first valve element by the first camshaft on this valve element is detected. An actual position of the first camshaft and/or of a crankshaft driving the latter is detected on the basis of this detecting of the effect. An adjustment of the first camshaft is calibrated on the basis of a first deviation between this detected actual position and a predetermined required position.