Narrative:

I was flying aircraft X from ZZZ to ZZZ1 via direct on an IFR flight plan; level at 5;000 ft. 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 (pounds per hour). 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 ft. During my climb to 8;000 ft. 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 [request priority handling.] I landed safely at ZZZ airport approximately 45 minutes after my departure.

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Original NASA ASRS Text

Title: Caravan Captain reported fuel flow and engine oil pressure anomalies and elected to return to departure airport.

Narrative: I was flying Aircraft X from ZZZ to ZZZ1 via direct on an IFR flight plan; level at 5;000 ft. 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 (pounds per hour). 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 ft. During my climb to 8;000 ft. 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 [request priority handling.] I landed safely at ZZZ airport approximately 45 minutes after my departure.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.