Some owners of 2019-2020 Mazda3 and CX-5 vehicles may complain about a surging at low speeds and during acceleration. This surging is in the longitudinal direction, felt about 2 cycles per second and occurs in the locked-up 1st gear. 

This may be caused by the torque fluctuation and the torsional resonance in the torque converter. 

To correct this concern, the PCM software has been modified to reduce the torque fluctuation. 

Reprogram the PCM using the Mazda Diagnostic and Repair Software (MDARS), refer to MDARS ECU reprogramming procedures.