Claims:We claim:

1. A method for determining fuel injection timing for an engine of a vehicle, the method comprising:
detecting, by an Electronic Control Unit (ECU) of the vehicle, upon receiving a request for cranking the engine for a first time, a reference position on a flywheel at two time intervals;
operating, by the ECU (318), a fuel injector (321) to inject fuel at a predetermined angle from the reference position at each of the two time intervals;
comparing, by the ECU (318), change in at least one of engine speed and acceleration at each the two time intervals; and
identifying, by the ECU (318), positions of the fuel injection at the two time intervals as at least one of compression Top Dead Centre (TDC) position and an exhaust TDC position of the engine, based on the comparison;
wherein, the ECU (318) is configured to inject the fuel at the one of the two time intervals identified as compression TDC position in subsequent stages.

2. The method as claimed in claim 1 comprising storing, by the ECU (318), in a memory unit (320) associated with the ECU (318), the compression TDC position as fuel injection timing.

3. The method as claimed in claim 1, wherein the reference position is detected by identifying a missing tooth on the flywheel.

4. The method as claimed in claim 3, wherein the missing tooth is identified through a crank sensor (319).

5. The method as claimed in claim 1, wherein the predetermined angle is in a range of about 110° to 120° from the reference position.

6. The method as claimed in claim 1, wherein a first-time interval of the two-time intervals is identified as the compression TDC position and a second time interval of the two-time intervals is identified as the exhaust TDC position when at least one of the engine speed and acceleration change is greater at the first-time interval than the second time interval.

7. The method as claimed in claim 1, wherein the second time interval of the two-time intervals is identified as the compression TDC position and the first-time interval is identified as the exhaust TDC position when at least one of the engine speed and acceleration change is greater at the second time interval than the first-time interval.

8. The method as claimed in claim 1, the method further comprising;
detecting, by the ECU (318), upon receiving a request for shutting off the engine for a first time, the reference position on the flywheel;
detecting, by the ECU (318), a previous reference position on the flywheel, when the engine revolution is less than a predetermined limit, based on the detection of shutting off the engine; and
detecting, by the ECU (318), a previous TDC position, and storing the previous TDC position in the memory unit (320) before the vehicle is shut off.

9. The method as claimed in claim 8, wherein the predetermined limit of revolution is less than 360? during engine shut off.

10. The method as claimed in claim8 comprises recalling, by the ECU (318), previous compression TDC position for subsequent start of the engine, and operating, by the ECU (318), the fuel injector (321) to inject fuel.

11. The method as claimed in claim 10 further comprises:
monitoring, by the ECU (318), start condition of the engine upon injection of the fuel;
erasing, by the ECU (318), previously stored data if the start condition of the engine is not detected upon injection of the fuel.

12. The method as claimed in claim 11, further comprises:
operating, by the ECU (318), the fuel injector (321) to inject fuel at a predetermined angle from the reference position at the next compression TDC position;
storing, by the ECU (318), in a memory unit (320) associated with the ECU (318), the compression TDC position as fuel injection timing;

wherein, the ECU (318) is configured to inject the fuel at the previous identified compression TDC position in subsequent stages.
, Description:TECHNICAL FIELD

The present disclosure relates in general to the field of automobiles. Particularly, but not exclusively, the present disclosure relates fuel injection timing control for an internal combustion engine of the vehicle. Further embodiments of the present disclosure disclose a method for determining fuel injection timing for internal combustion engine of the vehicle.

BACKGROUND

Combustion, also known as burning, is the basic process of releasing energy from a fuel and air mixture. In an internal combustion engine (ICE), the ignition and combustion of the fuel occurs within the engine cylinder itself. The fuel is injected into the cylinder of the engine via the fuel injectors and is ignited via compression ignition [in case of a diesel engine]. The fuel injection timing plays a crucial role in proper working of engine, specially the compression ignition engines. The synchronization of crank and cam shaft also plays a major role in proper combustion of fuel. The cam and the crank position sensors play a major role in the synchronisation of the cam and crank shaft and thereby determining an injection timing. The piston movement from TDC to BDC and vice versa is determined by the crank sensor. Cam shaft position sensor gives signal during cranking.

Conventionally, injection timing for the internal combustion engine is determined using a data from the cam and crank position sensor. The application of camshaft position sensors in internal combustion engine control is known generally in the engine control art. Camshaft position sensors and the hardware and software used to process camshaft position sensor signals typically provide information on engine angular position for synchronization of relative position sensor signals, such as signals output from engine crankshaft position sensors.

The crankshaft position sensor typically includes a magnetic reluctance or hall effect sensor positioned to sense passage of a missing tooth on the crankshaft. Unlike the engine output shaft, the camshaft rotates once for each engine cycle, and thus the sensed passage indicates engine angular position. Furthermore, the engine starting performance may be significantly reduced if the sensor or its associated hardware or software fails to operate properly.

The present disclosure is directed to overcome one or more limitations stated above or other such limitations associated with the conventional systems.

SUMMARY OF THE DISCLOSURE

One or more shortcomings of the conventional method and system are overcome by the method and the system as claimed and additional advantages are provided through the provision of the system as claimed in the present disclosure.

Additional features and advantages are realized through the techniques of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered a part of the claimed disclosure.

In one non-limiting embodiment of the disclosure a method for determining fuel injection timing for engine of a vehicle. The method includes detecting, by an Electronic control unit (ECU) a reference position on a flywheel upon receiving a request for cranking the engine for a first time. The reference position on the flywheel is detected at two-time intervals. The method further includes operating a fuel injector to inject fuel at a predetermined angle from the reference position at each of the two-time intervals. Once the fuel is injected at the two-time intervals, the ECU determines the speed change and compares the speed at two-time intervals. Further, the ECU identifies the positions of the fuel injected at two-time intervals as at least one of a compression top dead centre (TDC) position and an exhaust TDC position of the engine based on the speed comparison. The ECU is configured to inject fuel at the one of the two-time intervals which is identified as compression TDC position in the subsequent stages.

In an embodiment of the disclosure, the ECU stores the compression TDC position as fuel injection timing in the memory unit associated with the ECU.

In an embodiment of the disclosure, the reference position is detected by identifying a missing tooth on the flywheel.

In an embodiment of the disclosure, the predetermined angle is in a range of about 110° to 120° from the reference position.

In an embodiment of the disclosure, a first-time interval of the two-time intervals is identified as the compression TDC position and a second time interval of the two-time intervals is identified as the exhaust TDC position when the engine speed change is greater at the first-time interval than the second time interval.

In an embodiment of the disclosure, the second time interval of the two-time intervals is identified as the compression TDC position and the first-time interval is identified as the exhaust TDC position when the engine speed change is greater at the second time interval than the first-time interval.

In an embodiment of the disclosure, the method further includes detecting the reference position on the flywheel by the ECU, upon receiving a request for shutting off the engine for a first time. The method further comprises of detecting a previous reference position on the flywheel by the ECU, when the engine revolution is less than a predetermined limit based on the detection of shutting off the engine. Also, the method includes detecting of a previous compression TDC position by the ECU and storing the previous compression TDC position in the memory unit before the vehicle is shut off.

In an embodiment of the disclosure, the predetermined limit of revolution is less than or equal to 360? during engine shut off.

In an embodiment of the disclosure, the method further includes recalling previous compression TDC position by the ECU for subsequent start of the engine and operating the fuel injector to inject fuel.

In an embodiment of the disclosure, the method also includes monitoring by the ECU, the start condition of the engine upon injection of the fuel. The ECU erases the previously stored data if the start condition of the engine is not detected upon injection of the fuel.

In an embodiment of the disclosure, the method further includes operating the fuel injector to inject the fuel at a predetermined angle from the reference position at the next compression TDC. The ECU stores the compression TDC position as fuel injection timing, wherein the ECU is configured to inject the fuel at the previously identified compression TDC position in the subsequent stages.

It is to be understood that the aspects and embodiments of the disclosure described above may be used in any combination with each other. Several of the aspects and embodiments may be combined together to form a further embodiment of the disclosure.

The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF THE ACCOMPANYING FIGURES

The novel features and characteristic of the disclosure are set forth in the appended claims. The disclosure itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying figures. One or more embodiments are now described, by way of example only, with reference to the accompanying figures wherein like reference numerals represent like elements and in which:

FIG.1A is a flowchart of the method of determining fuel injection timing for an engine of a vehicle, in accordance with an embodiment of the present disclosure.

FIG.2 is a flowchart of the method of determining the last top dead centre (TDC) during the shutting off of the vehicle, in accordance with an embodiment of the present disclosure.

FIG.3 is a flowchart of the method of injecting the fuel during the subsequent start or stop of the engine, in accordance with an embodiment of the present disclosure.

FIG.4 illustrates a block diagram of system for determining fuel injection timing for an engine of a vehicle, in accordance with an embodiment of the present disclosure.

The figures depict embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.

DETAILED DESCRIPTION

The foregoing has broadly outlined the features and technical advantages of the present disclosure in order that the detailed description of the disclosure that follows may be better understood. Additional features and advantages of the disclosure will be described hereinafter which form the subject of the claims of the disclosure.

It should be appreciated by those skilled in the art that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other systems for carrying out the same purposes of the present disclosure. It should also be realized by those skilled in the art that such equivalent processes do not depart from the scope of the disclosure as set forth in the appended claims. The novel features which are believed to be characteristic of the disclosure, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present disclosure. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the figures, can be arranged, substituted, combined, and designed in a wide variety of different configurations, all of which are explicitly contemplated and make part of this disclosure.

Embodiments of the present disclosure describe a method for determining fuel injection timing for an engine of a vehicle. Conventionally, a reference from a cam sensor is used for determining a fuel injection timing. Accordingly, the present disclosure provides a method for determining fuel injection timing without use of cam sensor. The elimination of cam sensor provides advantages such as zero sensor or its associated hardware or software fails. Also, elimination of cam sensor saves hardware cost and associated software calibration issues.

In an embodiment, the method for determining fuel injection timing for an engine of a vehicle is disclosed. Once a request for cranking an engine is received by electronic control unit, cranking of engine begins. The crank shaft begins to rotate thereby rotating the flywheel associated with the crankshaft. A crank sensor is associated with both the ECU and crankshaft, the crank sensor detects the reference position on the flywheel. The detected reference position data is received by the ECU, the reference position may be a missing tooth on the flywheel. Once the reference position is detected the fuel is injected at a predetermined angle ranging from 110 degrees to 120 degrees. The fuel may be injected at two-time intervals to determine the compression and exhaust TDC positions and store it in the memory unit associated with the ECU. The ECU determines and compares the speed change between the two intervals in the engine after the fuel is injected. Based on the speed in the one of the two time intervals the ECU stores the positions as compression TDC or exhaust TDC position. In an embodiment, if the ECU identifies the speed in the first time interval is greater than the second time interval then the first time interval position is regarded as the compression TDC position and second time interval position is regarded as exhaust TDC position. In an embodiment, if the ECU identifies the speed in the second time interval is greater than the first time interval then the second time interval position is regarded as the compression TDC position and first time interval position is regarded as exhaust TDC position.

The ECU stores these positions in the memory unit associated with it in the form of TRUE or FALSE data. The ECU may be configured to inject fuel at one of the two time intervals which may be identified as compression TDC position in subsequent stages. Further, when the engine is being shut OFF for the first time, the ECU detects the and stores the reference position in the memory unit if the engine revolution per second is less than 360 degree, the ECU continues to detect the reference position. Once the engine revolutions per seconds may be below 360 degrees the previous reference position may be stored. The ECU also stores the position of the previous compression TDC in the memory unit. In an embodiment the ECU recalls the position of the previous compression TDC position for subsequent start of the engine and the engine is shut OFF.

Accordingly, during the cranking of the engine form the second time onwards when the crank request is received, the ECU recalls the previous compression TDC position from the memory and the cranking begins. For cranking it may be required an external cranking means such as a cranking motor which run on electric power from the battery. If the battery voltage is less than predetermined amount of voltage say 9 volts, the vehicle may be needed to be push started. Once the cranking is achieved by either normal cranking or push starting, the ECU detects the reference position and synchronizes the crank with the cam. The ECU further detects the position of the compression TDC and injects fuel at that position. If the engine is not started, the ECU continuously monitors the start condition until the cranking is achieved. If the cranking is not started the ECU erases the data form the associated memory unit and store the position of the current TDC as exhaust position and injects fuel when the ECU detects the next compression TDC position. The method for injecting fuel without any timing error is carried out without the provision of a cam position sensor, the crank and the cam are connected by a timing drive with helical gears or by synchronization belt or any other driving method.

The terms “comprises”, “comprising”, or any other variations thereof used in the specification, are intended to cover a non-exclusive inclusion, such that an assembly that comprises a list of components or steps does not include only those components or steps but may include other components or steps not expressly listed or inherent to such setup or method. In other words, one or more elements in an assembly proceeded by “comprises… a” does not, without more constraints, preclude the existence of other elements or additional elements in the assembly.

Henceforth, the present disclosure is explained with the help of one or more figures of exemplary embodiments. However, such exemplary embodiments should not be construed as limitation of the present disclosure. In the figures neither the vehicle nor the complete powertrain units is depicted for the purpose of simplicity. One skilled in the art would appreciate that the device may be employed in the internal combustion engine of any vehicle including but not limiting to passenger vehicles, commercial vehicles, machinery, earth moving machines and the like.

The following paragraphs describe the present disclosure with reference to FIGS.1-3. In the figures, the same element or elements which have similar functions are indicated by the same reference signs.

FIG.1 is an exemplary embodiment of the present disclosure, illustrating a flowchart of a method of determining the fuel ignition timing in the first start of the engine, where plurality of trials are performed to determine the injecting timing of the fuel at the right timing.

As illustrated in FIG.1, the method comprises one or more blocks illustrating a method for determining the fuel ignition timing in the first start of the engine. The method may be described in the general context of computer-executable instructions. Generally, computer-executable instructions can include routines, programs, objects, components, data structures, procedures, modules, and functions, which perform functions or implement abstract data types.

The order in which the method is described is not intended to be construed as a limitation, and any number of the described method blocks can be combined in any order to implement the method. Additionally, individual blocks may be deleted from the methods without departing from the spirit and scope of the subject matter described herein. Furthermore, the method can be implemented in any suitable hardware, software, firmware, or combination thereof.

As shown at 100, method includes detecting a reference position on a flywheel and operating the fuel injector (321) to inject fuel at a predetermined angle from the reference position at each of the two-time intervals by an electronic control unit (ECU) (318). The method further includes comparing the speed change at each of the two-time intervals after the fuel is injected. Further, the ECU (318) identifies the positions of the fuel injection at the two-time intervals as at least one of a compression top dead centre (TDC) position and an exhaust TDC position of the engine. The ECU (318) is configured to inject the fuel at the one of the two-time intervals identified as the compression TDC position in subsequent stages. As shown at 100, an engine cranking request is received by the ECU (318) for the first time. In an exemplary embodiment, the cranking may be achieved by at least on of an electric starting system, an air starting system or a hydraulic starting system. In an embodiment, crank of the engine may be attached to a cranking means such as but not limiting to a cranking motor. The cranking in the engine is achieved as shown at 101 after receiving the request for cranking. During running of the engine for first time, it may be necessary to determine the compression TDC position and the exhaust TDC position. Determining the compression TDC position plays a major role in determining fuel injecting, igniting and exhaust timings in the engine. In an embodiment, once the cranking is achieved a crank sensor (319) associated with the crank may be configured to detect a reference position on the fly wheel at two-time intervals as shown at 102a and 102b. In an embodiment, the reference position may be detected by identifying a missing tooth on the flywheel. The rotation of the crank shaft may be synchronized with the rotation of the cam shaft. In an embodiment, the crank shaft and the cam shaft are connected using a timing drive train with helical gears but not limiting to this particular dive arrangement.

Further as shown at 104a and 104b, the ECU (318) operates the fuel injector (321) associated with the engine ECU to inject fuel at a predetermined angle from the reference position at each of the two intervals. In an embodiment, the predetermined angle may be in the range of 110? to 120° from the reference position, but not limiting to this particular range of the predetermined angle. Some of the other factors influencing the angle of fuel injection may be the configuration of the engine, number of cylinders, valve train system type, valve timing, method of inhaling and type of intake systems in the engine. In the present disclosure the angle from the reference position at which the fuel may be injected may be 114°. In an embodiment, the injection timing of fuel may be dependent on several other factors not limiting to the angle of injection alone. The fuel maybe injected into the cylinders of the engine and maybe ignited to achieve a working stroke in the engine. As shown at 105a and 105b, the ECU (318) further determines the speed change in the engine when the fuel is injected and ignited at the two-time intervals. The speed determined by the ECU at the two-time intervals is compared as shown at 106. The ECU (318) based on the comparison of the speed identifies the position of the piston in the cylinder. As shown at 107 and 108, a first-time interval of the two-time intervals may be identified as at least one of the compression TDC or exhaust TDC position and second time interval position of the two-time intervals may be identified as at least one of the compression TDC or exhaust TDC position based on the speed of the engine. In an embodiment, if the engine speed or acceleration change is greater at the first-time interval than the second time interval then the first-time interval may be considered as compression TDC position and second time interval position as exhaust TDC position. In an embodiment, if the engine speed or acceleration change is greater at the second-time interval than the first-time interval then the second-time interval may be considered as compression TDC position and first-time interval position as exhaust TDC position. Further, a memory unit (320) associated with the ECU (318) [best shown in FIG.4] stores the compression TDC position and exhaust TDC position. In an embodiment, the compression TDC position and the exhaust TDC position may be stored in the form of TURE or FALSE in the memory unit (320). The ECU (318) may be configured to operate the injector to inject the fuel. The injector injects the fuel at the one of the two-time intervals identified as compression TDC in subsequent stages.

Referring now to FIG.2, which shows sequence of operations performed by the ECU (318), when an engine shut OFF request is received by the ECU (318) for the first-time [as shown at 200] after the ECU (318) has stored the compression and exhaust TDC position. Once the request for engine shut OFF is received, the crank sensor (319) associated with the crank detects the reference position on the flywheel. In an embodiment, the crank sensor (319) is associate with the ECU (318) [best shown in FIG.4]. The crank sensor (319) detects the revolution per second of the flywheel and this data is sent to the ECU (318). As shown at 202, if the detected revolutions per second in the rotation of the flywheel is less than 360?, the ECU (318) further detects the last reference position on the flywheel. The last reference detected by the ECU (318) as shown at 203 is stored in the memory unit (320) associated with the ECU (318). In an embodiment, the ECU (318) also detects previous TDC position and stores this previous TDC position in the memory unit (320) as shown at 203 and 204. The memory unit (320) associated with the ECU (318) stores the last reference position and the previous TDC position as shown at 205 before the engine is shut OFF.

Referring now to FIG.3, which is a flow chart of an embodiment of method of starting or cranking the engine during the subsequent start and shut OFF of the engine. In an embodiment, FIG.3 the flowchart for method of cranking the engine from the second time onwards is explained. As shown at 300, the ECU (318) receives the engine start or cranking request for the subsequent starts. After the engine cranking request is received by the ECU (318), as shown at 301 the ECU (318) recalls the previous TDC position stored in the memory unit (320) associated with it. In an embodiment, if the engine cranking fails to occur due to the low voltage or if the voltage in the battery is under specified limit, then the engine may be cranked by pushing the vehicle (as shown at 302 and 309). In an embodiment, if the battery voltage (V) is less than, but not limiting to 9V, then the vehicle may be push started. As shown at 304, the crank sensor (319) associated with the crank shaft detects the reference position on the flywheel. Further, the crank shaft may be synchronized with the cam shaft after the reference position is detected as shown at 305. In an embodiment, if the last TDC position stored in the memory is true then it is regarded as compression TDC position and the fuel may be injected after the predetermined angle from the reference position as shown at 307 and 308. In an embodiment, if the last TDC position stored is false then it is regarded as exhaust TDC and the injecting of fuel takes place during the next detection of the reference position as shown at 310. In an embodiment, the ECU (318) monitors start condition of the engine upon injection of fuel. If the start condition of the engine is not detected upon injection of fuel the ECU (318) erases the stored memory as shown at 313. In an embodiment, after the stored memory has been erased in the memory unit (320) associated with the ECU (318), the ECU (318) store the TDC position as the exhaust TDC position as shown at 314. Further, the fuel may be injected on the other TDC position, which may be regarded as the compression TDC position. Further, the stored memory is used to inject the fuel at the previous identified compression TDC position in subsequent stages (start and shut OFF).

In an embodiment, the present disclosure discloses a method for determining fuel injection timing in an engine of a vehicle without use of cam sensor. The elimination of cam sensor provides advantages such as low complexities and reduced number of components. Also, the elimination of cam sensor reduces the cost of hardware and related software calibration issues.

Equivalents

With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.

It will be understood by those within the art that, in general, terms used herein, are generally intended as "open" terms (e.g., the term "including" should be interpreted as "including but not limited to," the term "having" should be interpreted as "having at least," the term "includes" should be interpreted as "includes but is not limited to," etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding the description may contain usage of the introductory phrases "at least one" and "one or more" to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles "a" or "an" limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases "one or more" or "at least one" and indefinite articles such as "a" or "an" (e.g., "a" and/or "an" should typically be interpreted to mean "at least one" or "one or more"); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of "two recitations," without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to "at least one of A, B, and C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B, and C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to "at least one of A, B, or C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B, or C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase "A or B" will be understood to include the possibilities of "A" or "B" or "A and B."

While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated in the description

Referral Numerals:
FLOWCHART
Receiving crank request 100
Cranking 101
Reference position detection-1 102a
Reference position detection-2 102b
Crank synchronisation 103a
Crank synchronisation 103b
Injecting fuel at predetermined angle from reference position in first time interval 104a
Injecting fuel at predetermined angle from reference position in second time interval 104b
Determining speed change in first time interval 105a
Determining speed change in second time interval 105b
Comparing the speed change between the two-time intervals 106
If the speed of second interval is less storing it as exhaust TDC position 107
If speed of first-time interval is more storing that position as compression TDC position 108
Storing of compression and exhaust TDC position in the memory unit 109
Using the stored memory for subsequent stages 110
Receiving engine shut OFF request 200
Detecting reference position 201
Determining engine revolutions per second 202
Detecting the previous reference position 203
Identifying the last TDC position 204
Storing in memory the previous reference position and TDC position 205
Shutting OFF the engine 206
Receiving a start or crank request from the second start onwards 300
Recalling the last TDC from the ECU 301
Determining battery voltage 302
Engine cranking 303
Reference position detection 304
Synchronisation of crank 305
Determining the last TDC position 306
Compression TDC position 307
Injecting the fuel 308
Push starting is the battery voltage is low 309
Exhaust TDC position is the last TDC detected is TRUE 310
If engine is not started (start condition of engine) 311
Monitoring the start condition 312
Erase the current memory if the start condition is not achieved. 313
Storing the current position as exhaust TDC position 314
Injecting of fuel at the compression TDC 315
Store this TDC positions in the ECU 316
Using of the stored strategy for next start 317
Electronic control unit (ECU) 318
Crank sensor 319
Memory unit 320
Fuel injector 321
system 500