Scania Cv Ab

Scania Cv Ab (publ)

Roger Hälleberg

Kim Kylström

Anders Jensen

Ola Stenlåås

Klas Telborn

Magnus Pettersson

Tony Sandberg

Provided is a method for diagnosing unintended fuelling from one or more fuel injectors of a multi cylinder internal combustion engine during engine operation. Pressurized fuel is intended to be distributed by means of said fuel injectors from said accumulator tank to the cylinders for combustion. An oxidation catalyst is arranged downstream said cylinders. The method comprises: determining the pressure in the fuel accumulator tank and whether said pressure is decreasing; and determining whether the actual amount of fuel provided by the pump unit exceeds the demanded amount of fuel. The method further comprises the steps of: determining whether the temperature associated with the oxidation catalyst is above a certain level and/or determining whether the air/fuel ratio is below a certain level and/or determining whether an amount of particulate matter is above a certain level; and confirming an unintended fuelling based on the determined conditions.

Method and system for diagnosing unintended fuelling from fuel injectors of an engine

A method for determination of the bulk modulus of fuels in a fuel system of a combustion engine () with a common rail injection system (), with a high pressure volume () including the high pressure side of a high pressure pump () and a fuel accumulator () with injectors () for injection of fuel into the cylinders of the combustion engine. The method including: first determining the volume of the high pressure volume by supplying a fuel with a known bulk modulus to the fuel system and by controlling the high pressure pump () so that it performs a pump stroke with the volume of the high pressure volume closed. The value of the determined volume is later used with another fuel in order to determine the latter fuel's bulk modulus.

Method for determining the bulk modulus of fuels

A method for control of a vehicle's gearbox which is connected to a combustion engine and can be set to a number of different transmission ratios. When the vehicle is running in a low transmission ratio and at an engine speed below that at which the torque plateau for the low ratio is reached, in a situation where there is a reduced need for power output to propel the vehicle, determine a speed parameter for the vehicle, switch the gearbox to a higher transmission ratio than the low ratio when the speed parameter fulfills a first criterion.

Method and system for driving of a vehicle

A method for driving a vehicle in which a gearbox connected to a combustion engine can be set to various different transmission ratios including a low transmission ratio in which the engine speed is below that at which a torque plateau for the low ratio is reached. The vehicle may drive in a first mode or a second mode both at the low ratio, such that in the first mode, the vehicle is driven without fuel supply to the engine and in the second mode, the engine is provided with fuel supply in order to deliver motive force for propulsion of the vehicle. In the method one determines whether the vehicle should be driven according to the first mode or the second mode, based on a need for motive force.

A method for adjusting a lookup table that includes preset on-time values for an injector of an engine linked to fuel injection quantity values (&#x3b4;). The following steps are executed in a situation when the output shaft of the engine is disconnected from the output shaft of the gearbox. A torque loss value (T) and a combustion efficiency value (&#x3b5;) are determined or received. An actual fuel injection quantity value (&#x3b4;) is calculated, based on the torque loss value and the combustion efficiency value. An on-time value (tg) linked to the actual fuel injection quantity value is determined from the lookup table and the on-time value is compared with a presently applied on-time value (tb) that is established by an engine control with the aid of a regulator and the lookup table. The lookup table is adjusted based on the result of the comparison.

Method for adjusting a lookup table and a system for controlling an injector of a cylinder in a combustion engine

The present invention relates to the control of fuel pressure in a common rail engine in connection with an automatic gearshift procedure. Upon receipt of a primary gearshift command, a fuel pressure in the common rail fuel system is decreased. This decrease is initiated during a time interval prior to reducing engine torque. A gear is released after the engine torque is lowered, thereby enabling a smooth gear release.

Fuel pressure control in a common rail system

A method for adjusting an on-time calculation model or a lookup table used for determining on-time values for an injector of a cylinder in a combustion engine useful in a motor vehicle, where the injector is connected to a fuel accumulator. The method comprises the steps of injecting a test fuel quantity exceeding the maximum allowed fuel injection quantity under such conditions that no ignition of the injected fuel takes place; measuring the pressure drop in the fuel accumulator during the test injection; establishing the actual fuel quantity injected during the test injection based on the pressure drop; performing a comparison based on the actual fuel quantity or the corresponding on-time value established with the aid of the on-time calculation model or the lookup table; and adjusting the on-time calculation model or lookup table in dependence on the result of the comparison. An apparatus which performs the method. A computer program to perform the method.

Method for adjusting an on-time calculation model or lookup table and a system for controlling an injector of a cylinder in a combustion engine

The present invention relates to an engine speed indicator for a vehicle, which is driven by a combustion engine. The engine speed indicator comprises a first indicator arranged to show the actual member of revolutions of the engine and second indicator arranged to show at which number of revolutions or within which range of number of revolutions a minimal emission of at least one emission gas is obtained from the vehicle during operation of the combustion engine. The engine speed indicator also comprises a third indicator which is arranged to show an emission level of the emission gas at the actual value of the number of revolutions. A driver can hereby drive the vehicle in such a manner that the emissions of emission gases are substantially minimal.

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Nacka, Sweden

Roger Hälleberg