Need a smoother gen 2

I recently purchased a 2012 manual , 2.7 Tacoma through a dealer online . The previous owner has installed a afe air intake, 18”raceline wheels, custom bumpers, etc. Truck runs fine , but exhaust has a sporty rumble , I’m not really liking . Truck also has a rough shutter ( if I’m describing correctly), when I get rpms a bit low. Would you assume these issues would stem from the aftermarket intake ?

Id like this rig to be as smooth as possible at very low rpms . As well as stealthy quiet.

I’d love to hear any and all options from the experienced minds here at Tacomaworld.

Note:I’m no mechanic ,but I’ve driven a Toyota pickup since my first 81.

 

You should move this to the 2nd gen section.

 

Good place to post this would probably be in the 2nd gen section. Stumbling at low RPMs could be a LOT of things. I’d start with fresh gas.