Decrease in rpm during gear shift

[sohailgill]

I have xli 2016, for the last few days the rpm during gear shift gets very low, befor this it was around 800, 900 but now i goes to 300,400

Can anyone tell the reason please

[Kamando]

Step by step check or service

Check air filter
Check plugs
Check vacume leaks
Service throttle body
Service catalytic converter or ad additive to clean it
Service vvti solinoid valve
Service MAS sensor at air cleaner box
Get car scanned espcially check o2 sensor voltage .
Hopefully issue will be solved