Your IAC only minor idle speed adjustments. It wont have anything to do with sputtering.

The MAF can, but it controls fueling into the motor. So unless when its sputtering its blowing black smoke out the tail pipes.. probably ignition related.

Could also be a fuel pump going bad. But start on the easy stuff.. thats why I suggested plugs. You can tell a a lot about an engine looking at the spark plugs. If they all come out black and sooty.. then its a fueling issue. They pull out white.. then its lean=fuel system issue.

HTH