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Service bulletins for the 2020 Cadillac CT4

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.

888 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
N2023205102021-02-16. Service bulletin. LANE DEPARTURE; FUEL SYSTEM, GASOLINE; SERVICE BRAKES, HYDRAULIC; ELECTRICAL SYSTEM; AIR BAGS; ENGINE AND ENGINE COOLING; POWER TRAIN. Customer Satisfaction Program. Certain vehicles, equipped with a gas engine, may have a condition in which the printed circuit board inside of the water pump may have been manufactured incorrectly potentially causing a water pump failure. The vehicle coolant system temperature is monitored and will display multiple warnings to the customer as coolant temperatures rise. At a set coolant temperature, the MIL will illuminate, DTC P2B85 will set in the engine control module (ECM), the oil pressure gauge will indicate high oil pressure and reduced torque with notification to the driver of reduced power will occur. If the customer continues to drive after this warning and the coolant temperature continues to rise, a chime will occur, the AC will be disabled and an additional message instructing the driver to idle will illuminate. If the customer continues to drive the vehicle after all previous warnings and the coolant temperature continues to rise a message the engine will shut down could occur, and the engine will be shut down. Dealers are to replace the water pump.
050604022R2020-12-07. Service bulletin. FUEL SYSTEM, DIESEL. This bulletin provides information on the TOP TIER Detergent Gasoline Licensed Brands and the TOP TIER Diesel Fuel Licensed Brands that are recommended for use in all GM vehicles and the TOP TIER FUELS website URL.
20NA0982020-06-22. Service bulletin. ENGINE; FUEL SYSTEM, GASOLINE:FUEL INJECTION SYSTEM:INJECTORS. This informational bulletin explains to the tech on how to order a new fuel injector by matching the part number on the part and ordering it from the EPC.
16NA3832020-06-22. Service bulletin. ENGINE; FUEL SYSTEM, GASOLINE:FUEL INJECTION SYSTEM; EQUIPMENT ADAPTIVE/MOBILITY. This technical bulletin advises of a new fuel injection cleaner kit used for decarbonizing the intake valves to correct conditions of rough idle, Crank no start, extended crank or misfire, MIL with DTCs, and explains how Top Tier fuels should be used to reduce carbon build-up.
16NA3832020-03-02. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; EQUIPMENT; FUEL SYSTEM, GASOLINE:FUEL INJECTION SYSTEM. This informational bulletin advises of a new fuel injection cleaner kit used for decarbonizing the intake valves to correct conditions of rough idle, Crank no start, extended crank or misfire, MIL with DTCs, and explains how Top Tier fuels should be used to reduce carbon build-up.

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