My wife's old 09 cx9 did something similar and it turned out to be a misfire I've replaced coils, plugs, switched plug manufacturers twice,. It seemed to happen more at low rpm under load while the torque converter was locked (i.e
2011 Mazda CX-9 Overviews | Car Stoods
Experiencing a misfiring mazda engine
This guide breaks down common causes, diagnostic steps, and solutions to get your car running smoothly again.
After reading and searching, combined with multiple attempts at repair, i have a misfire code for cylinder #1 that won't go away