Caravan 208B
Flight Crew Commercial; Flight Crew Instrument
Flight Crew Last 90 Days 375; Flight Crew Total 2900; Flight Crew Type 300
Time Pressure; Workload; Distraction
Aircraft Equipment Problem Critical
Flight Crew Returned To Departure Airport; Flight Crew Landed in Emergency Condition
Aircraft
I was flying Aircraft X from ZZZ to ZZZ1 airport via direct on an IFR flight plan; level at 5;000 feet. It was a charter; empty out. One soul; 3.5 hours of fuel on board. A little over halfway to my destination; my fuel flow gauge began to rapidly fluctuate between 100-450 PPH. I turned my ignition and fuel boost on and checked both fuel tanks on; my fuel flow then began to fluctuate between 300-450 PPH; no other indications; annunciations; or failures at this time. I simultaneously requested to return to the ZZZ Airport and requested a higher altitude out of caution. I added power and initiated a climb to 8;000. During my climb to 8;000 my fuel flow began fluctuating again between 100-450 PPH accompanied by an oil pressure fluctuation between 85 and 100 PSI. Oil pressure unstable but maintaining within the green arc. There were no other failures or annunciations at this time. Given my inability to remedy the fluctuating gauges as well as the introduction of an oil pressure instability; I deemed it most appropriate to declare an emergency at this time. I landed safely at the ZZZ airport; approximately 45 minutes after my departure.
Cessna 208 Caravan pilot reported fluctuations in both fuel flow and engine oil pressure indications; resulting in a return to the departure airport.