C182 Pilot reported a sputtering engine during cruise led to an off field landing and a suspicion that fuel starvation may have been the cause.

Narrative

While enroute from ZZZ to ZZZ1; the engine suddenly began to sputter. I immediately switched the active fuel tank and increased the mixture to full rich. The engine began running normally for a short time it sputtered again with a drop in RPM; at this time I executed a safe precautionary off field landing; without any damage or injury.I suspect that there may have been a fuel system issue leading to fuel starvation which caused the engine to sputter. Several factors influence my analysis. First; at the time the issue occurred; I expected there to be approximately 1 hour of usable fuel remaining on board. I know the airplane well; and it always has a burn of 11 to 12 gallons per hour. This allows a minimum flight time of around 5 hours (including the 30-minute reserve). At the time of the issue; the aircraft had only been operating for less than 4 hours since last refueling. Second; there is a well-known issue with the Cessna 182 fuel caps. If not properly secured after refueling(which can be difficult); the fuel caps may allow fuel to escape during flight causing unknown quantities of fuel to exit the fuel tanks while simultaneously showing an erroneously high fuel quantity indication. I self-fueled at all except the last fuel stop prior to this event. I always check the fuel quantity visually; but cannot say for certain that I tightened the caps completely as I normally do. Third; the aircraft recently had its fuel bladders replaced. Although I cannot be sure; I suspect the new fuel bladders could have reduced the amount of usable fuel onboard. Another factor could be an incorrect installation resulting in fuel system leaks or ventilation issues. In the absence of a fuel issue; it is worth noting that I was intentionally operating at a richer than normal fuel mixture to combat a hotter than normal engine (yet still within all tolerances). Due to the hot temperature and low altitude; combined with heavy and gusting winds; the engine was hot. The increase mixture likely led to a higher than anticipated fuel burn. That said; fuel burn generally remains consistent at 11 to 12 gallons per hour; even when mixture is rich. To keep the engine at the appropriate temperature; I had to use some fuel for cooling; but I would not expect this to be a large factor in the hourly fuel use and certainly not enough to account for an additional hour of fuel consumed. After landing I added fuel; verified all preflight checks were complete; the aircraft and engine were operating normally; and then departed uneventfully. After arriving in ZZZ1; my Mechanic and I discussed the issue. Although at the time of this report; he had not inspected the plane; he is going to conduct a thorough inspection of the aircraft's fuel system. I have asked him to upgrade our fuel caps. Regardless of the issue; this is certainly a learning experience I will never forget. I plan to be overly cautious in the future regarding fuel planning. To prevent this recurrence; I will fly 3-hour legs maximum before refueling and I will assuredly be double checking not only whether it was fueled properly; but that the caps are in the full closed position physically.