Some Cadillac CT4 Units Require A Fuel Injector Flow Rate Fix

GM has issued a service update for a fix to a fuel injector flow rate issue affecting certain units of the 2020 through 2023 Cadillac CT4 sedan equipped with the turbocharged 2.7L I4 L3B gasoline engine.

Per Service Update N242450631, the affected Cadillac CT4 L3B engines may have a condition caused by “an Engine Control Module (ECM) that does not sufficiently control fuel injector flow rate under certain driving conditions.”

Notably, the turbocharged 2.7L I4 L3B engine is available as an optional powerplant choice for the Cadillac CT4 Premium Luxury trim level for the affected model years. The engine develops 310 horsepower and 350 pound-feet of torque in the CT4, while in the Cadillac CT4-V, the same engine is rated at 325 horsepower and 380 pound-feet of torque. In both cases, the L3B is connected to the GM 10-speed automatic transmission.

GM dealers are instructed to apply the available fix both to Cadillac CT4 units still in inventory and to those brought in for service. Dealership service personnel are to apply the fix promptly, and a courtesy vehicle must be provided to the CT4 owner if necessary while awaiting the repair. The fix is offered to owners free of charge through September 30^th, 2039.

The fix does not require any parts. Instead, it can be carried out by reprogramming the Engine Control Module (ECM) with the appropriate software. This fix requires about 12 minutes to verify and prepare for, and approximately 18 minutes to reprogram the ECM, or about half an hour in total. This should correct the issue and ensure a proper fuel injector flow rate.

Notably, the standard turbocharged 2.0L I4 LSY gasoline engine, rated at 237 horsepower and 258 pound-feet of torque and equipped on all three trim levels, is not included in this Service Update and is not subject to the flow rate issue. The sedans feature rear-wheel drive as standard and all-wheel drive as optional.

As a reminder, the Cadillac CT4 rides on the GM Alpha 2 platform, with production taking place at the GM Lansing Grand River plant in Michigan.