# US 10,480,431 B1 · Systems and methods for onboard canister purge valve flow mapping > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,480,431 B1 - Document ID: US10480431B1 - Status: Granted - Kind: B1 - Application number: 15/987,046 - Filed: 2018-05-23 - Published: 2019-11-28 - Granted: 2019-11-19 - Earliest claimed: 2018-05-23 - Assignees: Ford Global Technologies, LLC - Applicants: Ford Global Technologies, LLC - Inventors: Aed Dudar - Web page: https://patentgrep.com/patent/US10480431B1 ## CPC - F02D 41/0032: {Controlling the purging of the canister as a function of the engine operating conditions} - F02D 41/0045: {Estimating, calculating or determining the purging rate, amount, flow or concentration} - F02D 41/18: by measuring intake air flow - F02D 41/22: Safety or indicating devices for abnormal conditions {(in air/fuel ratio feedback systems F02D41/1495, in electric control linkage F02D11/107, in purge control systems F02M25/0809)} - F02M 25/0809: {Judging failure of purge control system} - F02M 25/0854: {Details of the absorption canister} - F02D 41/3082: {Control of electrical fuel pumps} - F02D 2041/224: {Diagnosis of the fuel system} - Y02T 10/40: Engine management systems - F02D: CONTROLLING COMBUSTION ENGINES (vehicle fittings, acting on a single sub-unit only, for automatically controlling vehicle speed B60K31/00; conjoint control of vehicle sub-units of different type or different function, road vehicle drive control systems for purposes other than the control of a single sub-unit B60W) - F02M: SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract Methods and systems are provided for indicating a presence or absence of degradation in a vehicle evaporative emissions system, where degradation includes a restriction in the evaporative emissions system and/or a source of undesired evaporative emissions. In one example, a method includes, under conditions where an engine is not combusting air and fuel, applying a pressure from the evaporative emissions system to an intake of the engine, and indicating an absence of degradation in the evaporative emissions system based on a test flow in the intake of the engine being within a predetermined threshold of a baseline flow obtained at an earlier time via applying the pressure. In this way, a presence or absence of degradation may be indicated without relying on engine operation. ## Claims ### Claim 1 A system for a hybrid vehicle, comprising: a fuel vapor storage canister positioned in an evaporative emissions system of the hybrid vehicle, the fuel vapor storage canister selectively fluidically coupled to a fuel system via a fuel tank isolation valve and selectively fluidically coupled to an intake of an engine via a canister purge valve; a throttle positioned in the intake of the engine; a plurality of intake valves configured to regulate air flow to the engine; a mass air flow sensor positioned in the intake of the engine; and a controller with computer readable instructions stored on non-transitory memory that when executed, cause the controller to: with the engine not combusting air and fuel, in a first condition, operate the evaporative emissions system in a first mode to direct a first test flow that is negative with respect to atmospheric pressure to the intake and indicate evaporative emissions system degradation in response to the first test flow being outside of a first predetermined threshold of a first baseline flow obtained via operating the evaporative emissions system in the first mode, where the first test flow and first baseline flow are indicated via the mass air flow sensor; and in a second condition, operate the evaporative emissions system in a second mode to direct a second test flow that is positive with respect to atmospheric pressure to the intake and indicate evaporative emissions system degradation in response to the second test flow being outside of a second predetermined threshold of a second baseline flow obtained via operating the evaporative emissions system in the second mode, where the second test flow and the second baseline flow are monitored via the mass air flow sensor. ### Claim 2 (depends on 1) The system of claim 1, further comprising: a pump positioned in the evaporative emissions system between the fuel vapor storage canister and atmosphere; and wherein the controller stores further instructions to, in the first condition, command fully open the canister purge valve, command fully closed the fuel tank isolation valve, command fully open the throttle, control the engine to substantially close the plurality of intake valves; and operate the pump at a predetermined speed to direct the first test flow to the intake, where the predetermined speed comprises a same speed as that utilized for obtaining the first baseline flow. ### Claim 3 (depends on 1) The system of claim 1, wherein the controller stores further instructions to, in the second condition, in response to a request for refueling of a fuel tank positioned in the fuel system, command fully open the fuel tank isolation valve to enable refueling of the fuel tank, and in response to an absence of premature shutoffs of a refueling dispenser during the refueling, and in response to an indication that a fuel fill rate comprises a predetermined fuel fill rate, direct the second test flow to the intake via commanding fully open the canister purge valve with the fuel tank isolation valve open, commanding fully open the throttle, and controlling the engine to substantially close the plurality of intake valves. ### Claim 4 A method, comprising: during a condition where an engine of a vehicle is not combusting air and fuel, applying a pressure from an evaporative emissions system of the vehicle to an intake of the engine; and indicating an absence of degradation in the evaporative emissions system based on a test flow in the intake of the engine being within a predetermined threshold of a baseline flow obtained at an earlier time via applying the pressure. ### Claim 5 (depends on 4) The method of claim 4, wherein a purge valve positioned in a purge line between the fuel vapor storage canister and the engine is commanded fully open, and wherein a throttle positioned in the intake is commanded fully open for obtaining the test flow and the baseline flow. ### Claim 6 (depends on 5) The method of claim 5, further comprising: adjusting operation of the purge valve while the engine is combusting air and fuel based at least in part on a presence or the absence of degradation in the evaporative emissions system. ### Claim 7 (depends on 4) The method of claim 4, wherein applying the pressure includes applying a negative pressure with respect to atmospheric pressure from the evaporative emissions system to the intake. ### Claim 8 (depends on 7) The method of claim 7, wherein a fuel vapor storage canister positioned in the evaporative emissions system is substantially clean of stored fuel vapors. ### Claim 9 (depends on 7) The method of claim 7, wherein a pump positioned in a vent line of the evaporative emissions system is controlled to a predetermined speed for applying the negative pressure to obtain the test flow and the baseline flow. ### Claim 10 (depends on 7) The method of claim 7, further comprising sealing a fuel system from the evaporative emissions system for obtaining the baseline flow and the test flow. ### Claim 11 (depends on 1) The method of claim 1, wherein applying the pressure includes applying a positive pressure with respect to atmospheric pressure from the evaporative emissions system to the intake. ### Claim 12 (depends on 11) The method of claim 11, wherein applying the positive pressure includes routing pressure generated during a refueling event of a fuel tank of the vehicle to the intake. ### Claim 13 A method, comprising: with an engine of a vehicle not combusting air and fuel, in a first condition operating an evaporative emissions system in a first mode to obtain a first test flow in an intake of the engine and indicating an absence of degradation of the evaporative emissions system in response to the first test flow being within a first threshold of a first baseline flow obtained at an earlier time via operating the evaporative emissions system in the first mode; and in a second condition, operating the evaporative emissions system in a second mode to obtain a second test flow in the intake of the engine and indicating the absence of degradation of the evaporative emissions system in response to the second test flow being within a second threshold of a second baseline flow obtained at an earlier time via operating the evaporative emissions system in the second mode. ### Claim 14 (depends on 13) The method of claim 13, wherein the first condition includes an indication that a refueling event is not in progress; and wherein the second condition includes an indication that a refueling event is in progress. ### Claim 15 (depends on 14) The method of claim 14, wherein a pressure-build from the refueling event in the second condition routes fluid flow to the intake of the engine; and wherein the second condition includes an indication of a predetermined fuel fill rate of a fuel tank. ### Claim 16 (depends on 14) The method of claim 14, wherein the second condition includes an absence of premature shutoffs of a refueling dispenser during the refueling event. ### Claim 17 (depends on 13) The method of claim 13, wherein operating the evaporative emissions system in the first mode and operating the evaporative emissions system in the second mode in both the first condition and the second condition, respectively, include commanding fully open a canister purge valve positioned in a purge line downstream of a fuel vapor storage canister, commanding fully open a throttle position in the intake, and controlling intake valves of the engine to substantially closed positions. ### Claim 18 (depends on 13) The method of claim 13, wherein operating the evaporative emissions system in the first mode in the first condition includes operation of a pump positioned in the evaporative emissions system, to draw a vacuum on the evaporative emissions system. ### Claim 19 (depends on 13) The method of claim 13, wherein the first condition includes an indication that a fuel vapor storage canister positioned in the evaporative emissions system is substantially free from stored fuel vapor, and where operating the evaporative emissions system in the first mode includes sealing the fuel system from the evaporative emissions system; and wherein operating the evaporative emissions system in the second mode includes fluidically coupling the evaporative emissions system to the fuel system. ### Claim 20 (depends on 13) The method of claim 13, further comprising indicating the first test flow, the first baseline flow, the second test flow, and the second baseline flow based on output of a mass air flow sensor positioned in the intake.