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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.

By type

By component

By trouble code

By topic

Only bulletins with component: Exhaust and emissions are shown. Show all

Bulletins, newest first
19-NA-0442024-02-21. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL; FUEL SYSTEM, GASOLINE. This service bulletin provides information on the cold start control system in DI engines to reduce cold start emissions and improve fuel economy.
N2323953102023-08-02. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL; FUEL SYSTEM, GASOLINE. Special Coverage - Certain vehicles may have a condition that could cause the evaporative emissions purge pump to fail. If this condition occurs, the Malfunction Indicator Light (Check Engine Light) will illuminate and a diagnostic trouble code will set. Dealers are to replace the evaporative emissions purge pump as necessary. The repairs will be made at no charge to the customer. The repairs will be made at no charge to the customer.
PIP5841C2023-04-17. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL:CRANKCASE (PCV). This Preliminary information communicates the potential for condensation to freeze up inside the Crankcase Pressure Sensor causing dtc P04FB to set.
PIP5841B2023-02-13. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL:CRANKCASE (PCV). This Preliminary information communicates the potential for condensation to freeze up inside the Crankcase Pressure Sensor causing dtc P04FB to set.
N2123295212021-06-14. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL. Emission Recall. General Motors has decided to conduct a voluntary emissions recall involving certain vehicles. The Vehicle Emissions Control Information (VECI) label may not contain the correct On-Board Diagnostic (OBD) system identifier. Since a new label can be easily installed, and to reduce customer inconvenience, the label will be sent directly to customers of record along with the installation instructions. Customers may install the label or, if they desire, they may take the label to their dealer for installation at no charge.
15NA0102020-03-02. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL. This informational bulletin provides information to dealership personnel for new vehicles with less than 1,000 miles that may not pass California smog inspection or smog inspection in other states.

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