2012 Toyota FJ Cruiser - Holds back

Hi, Have problem with my FJ feels like it’s holding back when drive it at slow speed around 80km/h not smoothly running as if I applied bit of brake on it and RPM suddenly increase and decrease when it holding back…When i drive more than 80km/h its ok and no problems.
Any suggestions what might be causing this? No weird sound or anything from engine or tires/suspension.FJ 2012.

Make sure the air intake hoses to the throttle body are not leaking, cracked, etc.
Check that the MAF sensor is not dirty.
Pour a bottle of fuel injector cleaner in the gas tank. Chevron /w Techron suggested.