2004 Mazda MPV hesitation

I have a 2004 Mazda MPV hesitation issue. While at idle and in gear there is a hesitation that happens every couple of seconds. I happens a little bit upon acceleration but quickly goes away at regular speeds. This also happens at idle while not in gear however the hesitation is less frequent. There are no trouble codes and the check engine light is not on. I can’t figure out what is wrong. Any ideas?? Thanks

Here are a few possibilities:

Faulty ignition system
Clogged or dirty fuel injectors
Low fuel pressure (check fuel system) When was the fuel filter last replaced?
Emissions fault
Maybe even a faulty IAC valve