CX-9 surging while coasting to a stop.
 

I wondeirng if some of you have had the same issue as I am currently having or can school me on the Mazda drivetrain as this if the first Mazda vehicle I have ever owned (45 yrs old). I have a 2013 CX-9 with about 140K and the car runs great except that the vehicle surges when down shifting between 35-25 mph while coasting to a stop. The surge is very prominent and makes it seem like theres a tranny issue. I purchased the vehicle used and have had it for almost a year. I recently did a throttle body clean and I am wondering if that is having an effect or do I need to clean the MAF sensor? Is this a cause for concern? Let me know.