Narrative:

Engine had roughness when flying; drained yellow fuel before flight; but did get blue fuel after continuous draining. Will ask a mechanic next time when the same thing happens. [I] diverted after engine roughness. Fix in progress.

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Original NASA ASRS Text

Title: PA44 pilot discovers yellow fuel when taking fuel samples during preflight; while expecting blue fuel. Engine roughness was noted in flight and reporter diverted for maintenance.

Narrative: Engine had roughness when flying; drained yellow fuel before flight; but did get blue fuel after continuous draining. Will ask a mechanic next time when the same thing happens. [I] diverted after engine roughness. Fix in progress.

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.