Narrative:

Aztec developed sudden right engine loss of power; likely due to fuel issue; but investigating now. Fuel flow dropped; aux pump activated and fuel tanks changed. While in IFR conditions; descended unintentionally to 8;000-8;500 ft; regained control; and reclimbed to 9;000. Event recurred 1 time within 10 min; and engine then regained power.requested 5;000 for duration of trip into VFR conditions at destination; rather than immediate landing into poor visibility and unfamiliar; small airport; as engine condition had stabilized. Landed uneventfully at ZZZ and plane to go for evaluation [3 days later]. I suspect fuel line issue; or possible ice crystal formation in line? All sumps tested pre and post flight; with no water discovered.

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Original NASA ASRS Text

Title: PA23 pilot experienced an unexplained power loss on the right engine at 9;000 feet. The aircraft was allowed to descend from assigned altitude while troubleshooting before engine power was restored and assigned altitude was regained. The event repeated within ten minutes; but the reporter elected to continue to the destination with VFR weather.

Narrative: Aztec developed sudden right engine loss of power; likely due to fuel issue; but investigating now. Fuel flow dropped; aux pump activated and fuel tanks changed. While in IFR conditions; descended unintentionally to 8;000-8;500 ft; regained control; and reclimbed to 9;000. Event recurred 1 time within 10 min; and engine then regained power.Requested 5;000 for duration of trip into VFR conditions at destination; rather than immediate landing into poor visibility and unfamiliar; small airport; as engine condition had stabilized. Landed uneventfully at ZZZ and plane to go for evaluation [3 days later]. I suspect fuel line issue; or possible ice crystal formation in line? All sumps tested pre and post flight; with no water discovered.

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.