P0300 ONLY @ Less than half a Tank of Gas
 

So as the title reads I have quite a unique situation going on with my 2007 L61 2.2L Supercharged Cobalt coupe.

The Car - 2007 L61 2.2L 5 Speed 56K Miles (Supercharged since ~19K miles)
- Supercharged Stage 2 (Belt, Injectors, Plugs and Pulley + big ass FMIC) (2009)
- LS2 Edit Dynotuned @ SMG Autosports (2009)
- Fresh (1k miles?) Fidanza custom oversized aluminum flywheel + GMPP LSJ clutch kit
- Full bolt-ons, fresh Denso 02 sensors, fresh fluids, fresh plugs, fresh filters
- Stock battery (never needed a jump over its 11 years so far :lol:)

The problem - P0300 CEL -> Random Misfire
ONLY throws the P0300 with under 1/2 a tank of fuel remaining. If I fill her up past halfway EVERY time the CEL disappears without clearing it or anything within a mile's drive (have been playing this game about 6 months but rarely drive this car)

Potential Culprits:
- Water in the tank - sitting on top of gas but is sucked in at lower volumes (car sits a lot, sometimes with very little fuel)
- Fuel filter is partially occluded -> more obvious at low volumes of gas due to decreased pressure exerted from the gas itself on the pump

Anyone on here run into a similar problem? Or have some advice given my observations?