The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 19, 2019
Filed:
Sep. 12, 2017
GM Global Technology Operations Llc, Detroit, MI (US);
Todd W Nelson, Brighton, MI (US);
GM GLOBAL TECHNOLOGY OPERATIONS LLC, Detroit, MI (US);
Abstract
A method for small leak testing of an evaporative emissions system includes monitoring a vacuum pressure level of the evaporation emissions system with the engine on and actuating a canister vent valve to regulate the vacuum pressure level to a predetermined minimum vacuum pressure level. Upon turning the engine off, the canister vent valve and a canister purge valve are closed to seal the evaporative emissions system. Next, the vacuum pressure level is recorded over a predetermined time period after turning off the engine and a fault code is set when the vacuum pressure level becomes less than the predetermined minimum vacuum pressure level.