Vehicle

Abstract

To easily diagnose an adhesion state of oil and fat in an exhaust flow passage.SOLUTION: A vehicle includes an engine, an exhaust passage communicating with the engine, an air-fuel ratio sensor provided in the exhaust passage, and a control device including one or more processors and one or more memories connected to the one or more processors, wherein the one or more processors are configured to execute a process including executing a back flow process of causing gas in the exhaust passage to flow back while the vehicle is stopped, and executing a diagnosis process of diagnosing an adhesion state of oil and fat in the exhaust passage based on a detection result of the air-fuel ratio sensor during execution of the back flow process.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a vehicle. [Background technology]

[0002] For example, as shown in Patent Documents 1 and 2, in the manufacturing process of engines for vehicles such as automobiles, a final inspection is carried out by conducting an operational test on all engines after assembly is completed. The operational test is also called a firing test.

[0003] In the manufacturing process of vehicles, industrial oils and greases are used for molding, processing, cleaning, and other processes of metal components. As a result, oil and grease may remain in the exhaust passage of the vehicle. If the engine is driven with oil and grease adhering to the exhaust passage, particulate matter derived from the oil and grease may be generated in the exhaust passage.

[0004] Therefore, in the past, in addition to the above-mentioned final inspection, all vehicles before shipping were subjected to a removal process to remove grease from the exhaust passage. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 08-254154 [Patent Document 2] Japanese Patent Application Publication No. 08-278191 Summary of the Invention [Problem to be solved by the invention]

[0006] However, the amount of grease adhering to the exhaust passage varies from vehicle to vehicle. Therefore, if a removal process that can reliably remove grease from all vehicles before shipment, as in the above-mentioned conventional technology, is performed in a similar manner, there is a problem that the removal process requires a lot of effort, time, and cost. Furthermore, if the removal process involves burning off the grease by running the engine to raise the exhaust gas temperature, there is also a problem that the engine's operating time before shipment is unnecessarily long. For this reason, there is a need for the development of a technology that can easily diagnose the state of grease adhering to the exhaust passage.

[0007] In view of the above problems, the present invention aims to provide a vehicle that can easily diagnose the state of grease adhesion in the exhaust passage. [Means for solving the problem]

[0008] In order to solve the above problem, a vehicle according to one embodiment of the present invention comprises: The engine and an exhaust passage communicating with the engine; an air-fuel ratio sensor provided in the exhaust flow path; a control device having one or more processors and one or more memories coupled to the processors; Equipped with The processor: performing a backflow process for causing gas in the exhaust passage to flow backward while the vehicle is stopped; performing a diagnostic process for diagnosing a state of adhesion of grease in the exhaust passage based on a detection result of the air-fuel ratio sensor during execution of the backflow process; Execute the process including. [Effects of the Invention]

[0009] According to the present invention, it is possible to easily diagnose the state of adhesion of grease inside the exhaust flow passage. [Brief explanation of the drawings]

[0010] [Figure 1]FIG. 1 is a schematic diagram showing a general configuration of a vehicle according to an embodiment of the present invention. [Figure 2] FIG. 2 is a block diagram showing an example of a functional configuration of a control device according to the embodiment. [Figure 3] 10 is a flowchart showing an example of a flow of processing performed by the control device according to the embodiment. [Figure 4] FIG. 4 is a schematic diagram showing a general configuration of a vehicle according to a first modified example. [Figure 5] FIG. 10 is a schematic diagram showing a general configuration of a vehicle according to a second modified example. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Specific dimensions, materials, numerical values, etc. shown in the embodiments are merely examples for facilitating understanding of the invention and do not limit the present invention unless otherwise specified. In this specification and drawings, elements having substantially the same functions and configurations are designated by the same reference numerals to avoid redundant explanation, and elements not directly related to the present invention are not shown.

[0012] <1. Vehicle configuration> First, the configuration of a vehicle 100 according to an embodiment of the present invention will be described with reference to Fig. 1. Fig. 1 is a schematic diagram showing a general configuration of a vehicle 100 according to an embodiment of the present invention. As shown in Fig. 1, the vehicle 100 includes, for example, an engine 110, an intake manifold 120, an intake flow path 130, an exhaust manifold 140, an exhaust flow path 150, an air-fuel ratio sensor 160, and a control device 190.

[0013] The engine 110 functions as a drive source for the vehicle 100. In other words, the vehicle 100 is an engine vehicle. The engine 110 is a gasoline engine or a diesel engine. The vehicle 100 may be a hybrid vehicle that includes a motor as a drive source in addition to the engine 110. The engine 110 has, for example, multiple cylinders.

[0014] The intake manifold 120 is connected to an intake port formed in each cylinder of the engine 110. The intake port is opened and closed by an intake valve 122.

[0015] The intake flow path 130 is connected to the engine 110 via the intake manifold 120. The intake flow path 130 is connected to a junction of the intake manifold 120. An air cleaner 132, for example, is provided in the intake flow path 130. The air cleaner 132 removes foreign matter contained in the air taken into the intake flow path 130. A throttle valve 134 is provided in the intake flow path 130 downstream of the air cleaner 132. The throttle valve 134 adjusts the flow rate of the intake air sent to the engine 110 through the intake flow path 130. The flow rate of the intake air sent to the engine 110 changes depending on the opening degree of the throttle valve 134.

[0016] The exhaust manifold 140 is connected to an exhaust port formed in each cylinder of the engine 110. The exhaust port is opened and closed by an exhaust valve 142.

[0017] The exhaust flow path 150 is connected to the engine 110 through the exhaust manifold 140. The exhaust flow path 150 is connected to a collecting portion of the exhaust manifold 140. The exhaust flow path 150 is provided with, for example, a purification device 152. The purification device 152 purifies the exhaust gas emitted from the engine 110. The purification device 152 includes, for example, one or both of a catalyst and a filter. The catalyst includes, for example, at least one of an oxidation catalyst, a three-way catalyst, and a NOx storage reduction catalyst. The filter captures particulate matter such as soot contained in the exhaust gas. The filter is, for example, a GPF or a DPF. The exhaust gas purified by the purification device 152 is discharged to the outside through a muffler 154.

[0018] The air-fuel ratio sensor 160 is provided in the exhaust flow path 150. For example, the air-fuel ratio sensor 160 is provided on the engine 110 side of the purification device 152 in the exhaust flow path 150. The air-fuel ratio sensor 160 detects the oxygen concentration in the exhaust gas. The air-fuel ratio sensor 160 includes, for example, an A / F sensor or an O2 sensor.

[0019] In this embodiment, the vehicle 100 may be equipped with an evaporated fuel treatment device 170. The evaporated fuel treatment device 170 is also called an evaporative system. The evaporated fuel treatment device 170 prevents fuel gas evaporated from a fuel tank or the like provided in the vehicle 100 from being released into the atmosphere. The evaporated fuel treatment device 170 includes, for example, a first flow path 172, a canister 174, a suction device 176, and a first opening adjustment valve 178.

[0020] The first flow path 172 is connected to the intake flow path 130. The canister 174 is provided in the first flow path 172. The canister 174 stores fuel gas evaporated from a fuel tank or the like. The canister 174 includes, for example, activated carbon.

[0021] The suction device 176 is provided in the first flow path 172 on the opposite side of the intake flow path 130 with respect to the canister 174, and sucks gas from the intake flow path 130 toward the first flow path 172. The suction device 176 is included in, for example, an ELCM (Evaporative Leak Check Module). The ELCM is a device that checks for fuel gas leaks from the fuel tank. The suction device 176 includes, for example, a pump.

[0022] The first degree of opening adjustment valve 178 is provided in the first flow path 172 on the intake flow path 130 side with respect to the canister 174. The first degree of opening adjustment valve 178 adjusts the flow path cross-sectional area of ​​the first flow path 172. The first degree of opening adjustment valve 178 is, for example, a solenoid valve.

[0023] In this embodiment, the vehicle 100 may also be equipped with an exhaust gas recirculation device 180. The exhaust gas recirculation device 180 is also called an EGR (Exhaust Gas Recirculation) device. The exhaust gas recirculation device 180 reduces nitrogen oxides in the exhaust gas by recirculating the exhaust gas to the engine 110 through the intake passage 130. The exhaust gas recirculation device 180 includes, for example, a second passage 182, an EGR cooler 184, and a second opening adjustment valve 186.

[0024] The second flow path 182 connects the exhaust flow path 150 and the intake flow path 130. In this embodiment, the second flow path 182 is connected to the exhaust manifold 140 side of the exhaust flow path 150 relative to the purification device 152. The second flow path 182 is also connected to the intake flow path 130 relative to the throttle valve 134 relative to the intake manifold 120.

[0025] The EGR cooler 184 is provided in the second passage 182. The EGR cooler 184 cools the exhaust gas flowing through the second passage 182.

[0026] The second opening adjustment valve 186 is provided in the second flow path 182. For example, the second opening adjustment valve 186 is provided in the second flow path 182 on the intake flow path 130 side with respect to the EGR cooler 184. The second opening adjustment valve 186 adjusts the flow path cross-sectional area of ​​the second flow path 182.

[0027] The control device 190 has one or more processors 190a and one or more memories 190b connected to the processors 190a. The processor 190a includes, for example, a CPU (Central Processing Unit). The memory 190b includes, for example, a ROM (Read Only Memory) and a RAM (Random Access Memory). The ROM is a storage element that stores programs used by the CPU, calculation parameters, etc. The RAM is a storage element that temporarily stores data such as variables and parameters used in processing executed by the CPU.

[0028] The control device 190 communicates with each device provided in the vehicle 100, such as the engine 110, the throttle valve 134, the air-fuel ratio sensor 160, the suction device 176, the first opening adjustment valve 178, and the second opening adjustment valve 186. The communication between the control device 190 and each device is realized, for example, using CAN (Controller Area Network) communication.

[0029] Fig. 2 is a block diagram showing an example of the functional configuration of the control device 190 according to this embodiment. For example, as shown in Fig. 2, the control device 190 has an acquisition unit 192 and a control unit 194. Note that various processes, including the processes described below, performed by at least one of the acquisition unit 192 and the control unit 194 may be executed by the processor 190a. In detail, the various processes are executed by the processor 190a executing a program stored in the memory 190b.

[0030] The acquisition unit 192 acquires various information used in the processing performed by the control unit 194, and outputs the information to the control unit 194. For example, the acquisition unit 192 acquires information from the air-fuel ratio sensor 160.

[0031] The control unit 194 controls the operation of each device provided in the vehicle 100. In this embodiment, the control unit 194 executes a backflow process to cause gas in the exhaust flow path 150 to flow backward while the vehicle 100 is stopped. The control unit 194 then executes a diagnosis process to diagnose the state of grease adhesion in the exhaust flow path 150 based on the detection result of the air-fuel ratio sensor 160 while the backflow process is being executed. The control unit 194 may also execute a removal process to remove grease from the exhaust flow path 150 depending on the result of the diagnosis process. The backflow process, diagnosis process, and removal process executed by the control unit 194 will be described in detail below.

[0032] The functions of the control device 190 according to this embodiment may be divided among multiple devices, or multiple functions may be realized by one device. When the functions of the control device 190 are divided among multiple devices, the multiple devices may be connected to each other via a communication bus such as a CAN.

[0033] <2. Operation of the control device> Next, the operation of the control device 190 according to the embodiment of the present invention will be described with reference to FIG.

[0034] Fig. 3 is a flowchart showing an example of the flow of processing performed by the control device 190 according to this embodiment. The control flow shown in Fig. 3 is started, for example, while the vehicle 100 is stopped after starting and running that is performed before shipping the vehicle 100, while the vehicle 100 is stopped before starting and running that is performed before shipping the vehicle 100, or while the vehicle 100 is stopped after a new exhaust flow path 150 is attached to the vehicle 100.

[0035] When the control flow shown in FIG. 3 starts, first, in step S110, the control unit 194 executes a backflow process to reverse the gas in the exhaust flow path 150 while the vehicle 100 is stopped. In this embodiment, the control unit 194 reverses the gas in the exhaust flow path 150 by opening the first aperture adjustment valve 178 of the evaporated fuel treatment device 170 and driving the suction device 176. Generally, when the vehicle 100 is stopped, the intake valve 122 and the exhaust valve 142 are closed. Therefore, in the backflow process, the control unit 194 opens the second aperture adjustment valve 186 of the exhaust gas recirculation device 180. As a result, the gas in the exhaust flow path 150 and the outside air are caused to flow by the suction device 176 in the following order: exhaust flow path 150, air-fuel ratio sensor 160, second flow path 182, intake flow path 130, first flow path 172, and canister 174. Furthermore, in the backflow process, the control unit 194 preferably closes the throttle valve 134. This allows the control unit 194 to efficiently perform the backflow of gas.

[0036] Next, in step S112, the control unit 194 executes a diagnosis process to diagnose the state of grease adhesion in the exhaust flow path 150 based on the detection result of the air-fuel ratio sensor 160 while the backflow process is being executed. Specifically, the acquisition unit 192 acquires the detection value of the air-fuel ratio sensor 160. Then, the control unit 194 calculates the amount of grease adhesion in the exhaust flow path 150 based on the detection value of the air-fuel ratio sensor 160.

[0037] During the manufacturing process of the exhaust flow path 150, industrial grease adhering to the inside of the exhaust flow path 150 can be detected by the air-fuel ratio sensor 160, similar to the fuel of the vehicle 100. When industrial grease is adhering to the inside of the exhaust flow path 150, the excess air ratio (λ) detected by the air-fuel ratio sensor 160 will be less than 1.0. In other words, the greater the amount of industrial grease adhering to the inside of the exhaust flow path 150, the smaller the excess air ratio detected by the air-fuel ratio sensor 160.

[0038] Then, the control unit 194 determines whether the calculated amount of attached grease is equal to or greater than a threshold value. The threshold value is determined based on, for example, the amount of grease at which the amount of particulate matter derived from grease becomes less than the value specified in exhaust gas regulations.

[0039] When the control unit 194 determines that the calculated amount of adhesion of grease is equal to or greater than the threshold (YES in step S112), it ends the backflow process and the diagnosis process, and proceeds to step S114. On the other hand, when the control unit 194 determines that the calculated amount of adhesion of grease is not equal to or greater than the threshold, that is, is less than the threshold (NO in step S112), it ends the backflow process and the diagnosis process, and ends the control flow shown in FIG.

[0040] In step S114, the control unit 194 executes a removal process to remove grease from the exhaust flow path 150. For example, in the removal process, the control unit 194 removes grease from the exhaust flow path 150 by using exhaust gas emitted from the engine 110. Specifically, the control unit 194 operates the engine 110 and increases the rotation speed of the engine 110 to a higher speed than during normal operation, thereby increasing the temperature of the exhaust gas, thereby volatilizing the grease in the exhaust flow path 150 or burning off the grease. Note that at this time, the control unit 194 may perform lean combustion of the engine 110. This allows the control unit 194 to remove the grease from the exhaust flow path 150. Furthermore, the control unit 194 may adjust the temperature of the exhaust gas, the air-fuel ratio of the engine 110, the execution time of the removal process, and the like, taking into account the amount of attached grease.

[0041] Then, when step S114 is completed, the control unit 194 ends the control flow shown in FIG.

[0042] <3. Vehicle Effects> Next, the effects of the vehicle 100 according to the embodiment of the present invention will be described.

[0043] A vehicle 100 according to this embodiment includes an engine 110, an exhaust flow path 150 connected to the engine 110, an air-fuel ratio sensor 160 provided in the exhaust flow path 150, and a control device 190 having one or more processors 190a and one or more memories 190b connected to the processor 190a. The processor 190a executes a process, while the vehicle 100 is stopped, including: performing a backflow process to reverse the flow of gas in the exhaust flow path 150; and performing a diagnostic process to diagnose the state of grease and oil adhesion in the exhaust flow path 150 based on the detection result of the air-fuel ratio sensor 160 during the backflow process. By performing the backflow process, the vehicle 100 according to this embodiment can transport gas containing components volatilized from grease and oil adhered to the exhaust flow path 150 to the air-fuel ratio sensor 160. As described above, industrial grease and oil adhered to the exhaust flow path 150 during the manufacturing process of the exhaust flow path 150 can be detected by the air-fuel ratio sensor 160, similar to the fuel for the vehicle 100. Therefore, the vehicle 100 according to this embodiment can diagnose the state of grease adhesion in the entire area of ​​the exhaust flow path 150 from the air-fuel ratio sensor 160 to the outlet of the muffler 154 using the air-fuel ratio sensor 160. Therefore, the vehicle 100 according to this embodiment can easily diagnose the state of grease adhesion in the exhaust flow path 150 by simply performing a simple operation of causing gas in the exhaust flow path 150 to flow backward.

[0044] Furthermore, the processor 190a according to the present embodiment preferably executes a process that includes performing a removal process to remove grease from the exhaust flow path 150 in accordance with the results of the diagnostic process. As a result, in the present embodiment, the removal process can be performed only on vehicles 100 in which the amount of grease adhering to the exhaust flow path 150 is equal to or greater than a threshold. In other words, in the present embodiment, the removal process can be omitted for vehicles 100 in which the amount of grease adhering to the exhaust flow path 150 is less than the threshold. Therefore, in the present embodiment, it is possible to reduce the effort, time, and cost required for the removal process compared to conventional techniques in which the removal process is performed on all vehicles before shipment. Furthermore, in the present embodiment, it is possible to avoid a situation in which the mileage of vehicles 100 before shipment in which the removal process is omitted is unnecessarily extended.

[0045] Furthermore, the vehicle 100 according to this embodiment includes an intake flow path 130 that communicates with the engine 110, a first flow path 172 that is connected to the intake flow path 130 and has a canister 174 provided therein, a first aperture adjustment valve 178 that is provided in the first flow path 172 on the intake flow path 130 side relative to the canister 174, and a suction device 176 that is provided in the first flow path 172 on the opposite side of the canister 174 from the intake flow path 130 and that draws gas from the intake flow path 130 toward the first flow path 172, and the processor 190a preferably performs a process that includes causing gas in the exhaust flow path 150 to flow backward by opening the first aperture adjustment valve 178 and driving the suction device 176 during the backflow process. This enables the vehicle 100 according to this embodiment to perform the backflow process with a simple process.

[0046] <4. Modifications> The configuration of vehicle 100 has been described above with reference to Fig. 1. However, the configuration of the vehicle according to the present invention is not limited to the example shown in Fig. 1, and components of vehicle 100 described above may be deleted, changed, or added as appropriate.

[0047] <4.1. First Modification> For example, the configuration of the vehicle according to the present invention may be the configuration shown in Fig. 4. Fig. 4 is a schematic diagram showing the general configuration of a vehicle 200 according to a first modified example. As shown in Fig. 4, the vehicle 200 differs from the above-described vehicle 100 in that it is not provided with an exhaust gas recirculation device 180. Note that components that are substantially the same as those in the above-described vehicle 100 are given the same reference numerals and descriptions thereof will be omitted.

[0048] In the vehicle 200 shown in FIG. 4, when stopping the vehicle 200 prior to the backflow process, the control unit 194 stops the engine 110 in a valve overlap state in which both the intake valve 122 and the exhaust valve 142 are open in at least one cylinder of the engine 110. For example, when stopping the vehicle 200 before the start of the control flow of FIG. 3, the control unit 194 controls the engine 110 to be in the valve overlap state. The control unit 194 can stop the engine 110 in the valve overlap state, for example, by controlling the rotational angle of the engine 110 to be a rotational angle that results in the valve overlap state. Then, in the backflow process, the control unit 194 opens the first opening adjustment valve 178 and drives the suction device 176 while the engine 110 is controlled in the valve overlap state. As a result, the suction device 176 causes the gas in the exhaust flow path 150 and the outside air to flow through the exhaust flow path 150, the air-fuel ratio sensor 160, the exhaust manifold 140, the engine 110, the intake manifold 120, the intake flow path 130, the first flow path 172, and the canister 174 in this order. Furthermore, in the backflow processing, the control unit 194 preferably closes the throttle valve 134. This allows the control unit 194 to efficiently perform the backflow of gas.

[0049] In this way, the vehicle 200 according to the first modification can perform the backflow process with a simple process.

[0050] <4.2. Second Modification> Furthermore, the configuration of the vehicle according to the present invention may be, for example, the configuration shown in Fig. 5. Fig. 5 is a schematic diagram showing the general configuration of a vehicle 300 according to a second modified example. As shown in Fig. 5, the vehicle 300 differs from the above-described vehicle 100 in that an exhaust flow path valve 156 is provided, but an evaporated fuel treatment device 170 is not provided. Note that components that are substantially the same as those in the above-described vehicle 100 are given the same reference numerals, and description thereof will be omitted.

[0051] 5, the exhaust flow path valve 156 is provided downstream of the air-fuel ratio sensor 160 in the exhaust flow path 150. For example, the exhaust flow path valve 156 is provided between the purification device 152 and the muffler 154 in the exhaust flow path 150. The exhaust flow path valve 156 opens and closes the exhaust flow path 150.

[0052] In the vehicle 300 shown in FIG. 5 , the control unit 194 closes the exhaust flow path valve 156 when stopping the vehicle 200 prior to the reverse flow process. For example, when stopping the vehicle 300 before the start of the control flow of FIG. 3 , the control unit 194 closes the exhaust flow path valve 156. Then, in the reverse flow process, the control unit 194 closes the exhaust flow path valve 156 and opens the second opening adjustment valve 186, thereby causing gas in the exhaust flow path 150 to reverse flow. Specifically, in the second modified example, when stopping the vehicle 300, the control unit 194 closes the exhaust flow path valve 156 while the engine 110 is running, filling the exhaust flow path 150 with exhaust gas and increasing the pressure in the exhaust flow path 150. Note that at this time, it is preferable that the control unit 194 perform lean combustion of the engine 110. This allows the air-fuel ratio sensor 160 to detect grease with high accuracy. When the pressure in the exhaust passage 150 becomes higher than atmospheric pressure, the control unit 194 stops the engine 110.

[0053] After stopping the engine 110, the control unit 194 opens the second opening adjustment valve 186 while keeping the exhaust flow path valve 156 closed. At this time, the control unit 194 preferably opens the throttle valve 134. As a result, the exhaust gas in the exhaust flow path 150 flows in the following order: exhaust flow path 150, air-fuel ratio sensor 160, second flow path 182, and intake flow path 130, due to the pressure difference between the pressure in the exhaust flow path 150 and the pressure in the intake flow path 130 (atmospheric pressure).

[0054] In this way, the vehicle 300 according to the second modification can perform the backflow process with a simple process.

[0055] While the preferred embodiments of the present invention have been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to such embodiments. It is clear that those skilled in the art can conceive of various modifications and alterations within the scope of the claims, and it is understood that such modifications and alterations also fall within the technical scope of the present invention.

[0056] For example, the processes described herein using flowcharts do not necessarily have to be performed in the order shown in the flowcharts, and additional process steps may be employed or some process steps may be omitted.

[0057] In the above embodiment, the processor 190a executes the removal process when the amount of grease adhering is equal to or greater than the threshold. However, even when the amount of grease adhering is equal to or greater than the threshold, the processor 190a does not have to execute the removal process. When the amount of grease adhering is equal to or greater than the threshold, for example, the grease in the exhaust passage 150 may be removed by an operator.

[0058] In the above embodiment, the processor 190a estimates the amount of grease adhering to the exhaust passage 150 based on the detection value of the air-fuel ratio sensor 160. However, the processor 190a does not have to estimate the amount of grease adhering from the detection value of the air-fuel ratio sensor 160. For example, the processor 190a may determine whether or not grease is adhering directly from the detection value of the air-fuel ratio sensor 160. Furthermore, the processor 190a may determine whether or not the amount of grease adhering is equal to or greater than a threshold value directly from the detection value of the air-fuel ratio sensor 160. [Explanation of symbols]

[0059] 100 vehicles 110 Engine 122 Intake valve 130 intake passage 142 Exhaust valve 150 Exhaust flow path 156 Exhaust flow path valve 160 Air-fuel ratio sensor 172 First Channel 174 canister 176 Suction device 178 First opening adjustment valve 182 Second Channel 186 Second opening adjustment valve 190 Control Device 190a processor 190b memory 200 vehicles 300 vehicles

Claims

1. The engine and an exhaust passage communicating with the engine; an air-fuel ratio sensor provided in the exhaust flow path; a control device having one or more processors and one or more memories coupled to the processors; Equipped with The processor: performing a backflow process for causing gas in the exhaust passage to flow backward while the vehicle is stopped; performing a diagnostic process for diagnosing a state of adhesion of grease in the exhaust passage based on a detection result of the air-fuel ratio sensor during execution of the backflow process; A vehicle that performs processing including:

2. The vehicle according to claim 1 , wherein the processor executes a process including executing a removal process to remove the grease from the exhaust passage in response to a result of the diagnostic process.

3. an intake passage communicating with the engine; a first flow path connected to the intake flow path and including a canister; a first opening adjustment valve provided in the first flow path on the intake flow path side with respect to the canister; a suction device provided in the first flow path on an opposite side of the canister from the intake flow path, the suction device suctioning gas from the intake flow path toward the first flow path; Equipped with 3. The vehicle according to claim 1, wherein the processor, in the backflow process, executes a process including opening the first opening adjustment valve and driving the suction device to cause gas in the exhaust flow path to flow back.

4. 4. The vehicle according to claim 3, wherein the processor, in the backflow processing, executes processing including opening the first opening adjustment valve and driving the suction device while controlling the engine to a valve overlap state in which both an intake valve and an exhaust valve are open in at least one cylinder of the engine.

5. an intake passage communicating with the engine; a second flow path that communicates the exhaust flow path and the intake flow path; a second opening adjustment valve provided in the second flow path; an exhaust flow path valve provided in the exhaust flow path downstream of the air-fuel ratio sensor; Equipped with 3. The vehicle according to claim 1, wherein the processor executes a process in the backflow process that includes opening the second opening adjustment valve while keeping the exhaust flow path valve closed, thereby causing gas in the exhaust flow path to flow back.

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