Hesitation, Sag, Stumble

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2018 GMC Yukon XL, 2018 GMC Yukon, 2018 Chevrolet Tahoe, 2018 Chevrolet Suburban, and 2018 Cadillac Escalade ESV. However, it is still accessible from the selected car via links, so may be relevant.

Test the fuel pressure. Refer to Fuel System Diagnosis for fuel pressure specifications and testing procedures..
Test the generator. Refer to Symptoms - Engine Electrical . Repair the charging system if the generator output voltage is less than 9 volts or more than 16 volts.
Test the manifold absolute pressure (MAP) sensor. Refer to DTC P0106 .