Narrative:

[I] observed engine hesitation at 6;500 MSL with approximately 3.5 hours fuel remaining. Applied carburetor heat engine continued to hesitate. Declared emergency and followed checklist diverting to [nearest suitable airport]. Engine wind milled out and surged from stop to 2;500 RPM. After 2-4 minutes engine performed normally; however I continued emergency landing procedures and brought aircraft to full and controlled stop. We are consulting with maintenance regarding problem. [At the] last fuel stop [tanks were filled]. [I] clear and unrestricted visibility and no observed ceilings during all phases of flight.

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Original NASA ASRS Text

Title: A C150 pilot reported engine problems with surging and hesitating. He declared an emergency and diverted to the nearest suitable airport.

Narrative: [I] observed engine hesitation at 6;500 MSL with approximately 3.5 hours fuel remaining. Applied carburetor heat engine continued to hesitate. Declared emergency and followed checklist diverting to [nearest suitable airport]. Engine wind milled out and surged from stop to 2;500 RPM. After 2-4 minutes engine performed normally; however I continued emergency landing procedures and brought aircraft to full and controlled stop. We are consulting with maintenance regarding problem. [At the] last fuel stop [tanks were filled]. [I] clear and unrestricted visibility and no observed ceilings during all phases of flight.

Data retrieved from NASA's ASRS site as of April 2012 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.