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Service bulletins for the 2021 Kenworth W990

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

54 on file from NHTSA, as of 2026-10-19.

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Only bulletins with component: Fuel system are shown. Show all

Bulletins, newest first
E3062023-11-10. Service bulletin. FUEL SYSTEM, DIESEL. PACCAR MX-11 & MX-13 EPA2021 Fuel Filter Drain & Change Info Incorrect fuel filter drain and replacement procedures on EPA21 MX-11 and MX-13 engines can result in the following Debris and contaminants introduced into the high-pressure fuel system. Denial of warranty claims for injector and/or fuel system faults. Misfire, rough running, engine knock, and other associated faults and symptoms. Correct fuel filter procedures are outlined in attached service documentation.
E2902023-07-05. Service bulletin. FUEL SYSTEM, GASOLINE; ENGINE AND ENGINE COOLING. FIX-AS-FAIL Updated procedures and claim filing information. EPA2021 injector cleaning is referenced in RMI for certain injector faults. Complete the procedures in E290. Refer to E300 for in-tank additive information
03-087 (E295)2023-03-06. Service bulletin. FUEL SYSTEM, OTHER:FUEL FILTER; ENGINE AND ENGINE COOLING. Certain Model Year 2021-2024 chassis with PACCAR MX engines and optional fuel filter restriction virtual gauge may display incorrect restriction levels. The virtual gauge will be temporarily disabled until a revised sensor strategy is developed.
43-0712021-10-05. Service bulletin. FUEL SYSTEM, DIESEL. Fix-As-Fail – Due to undersupply issues, only a limited supply of Diesel Exhaust Fluid (DEF) sensors are available. As a temporary solution, after PACCAR confirms a DEF sensor is not available, a temporary software update will allow a vehicle to continue operation with a failed DEF sensor by disabling the DEF sensor diagnostics.

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.