Bone stock, no mods?
IF you had a noticeable difference after the cleaning, the first thing I would do is to take your pump out and clean it (if you didn't do this already). On the same day, I would probably install an inline fuel filter (make sure it is fuel injection, hopefully a clear plastic one so you can see if debris is getting caught, meaning your tank is still the problem).
It doesn't make much sense for the problem to go away for a week after cleaning, and then come back if it's not a debris in fuel problem. The inline filter should fix it and let you know if it's the problem. If that's not it, I'd come back with more info and try a few more things. (maybe getting the injectors professionally cleaned. also, might as well change the plugs while you're there. *this is all assuming you don't have kinked lines.)