ALEXANDRIA, Va., Sept. 23 -- United States Patent no. 12,421,927, issued on Sept. 23, was assigned to Daimler Truck North America LLC (Portland, Ore.).

"Cleaning, maintaining, refurbishing, and/or diagnosing engine components including fuel-injectors" was invented by John Joseph James Michalek (Dexter, Mich.) and John McNeill (Belle River, Canada).

According to the abstract* released by the U.S. Patent & Trademark Office: "Cleaning, maintaining, refurbishing, and/or diagnosing engine components including fuel system components, e.g., such as fuel-injectors. In one embodiment, a method of cleaning a fuel system component is provided. The method includes supplying a cleaning solution through the fuel system component, discontinuing the supp...