Narrative:

Taxied out and did run up and all was normal. Cleared for takeoff and added power. Manifold pressure (mp) came up and on rotation mp continued to climb and max out. I reduced the power in attempt to reduce mp but no reduction. As I climbed out ATC notified us of smoke out of the left engine so I immediately took control of the aircraft and began a rerun to landing. As I reduced power mp dropped down to normal and the smoke stopped so I continued with a normal landing and taxied back to the gate and deplaned the passengers. No other incidents occurred.

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Original NASA ASRS Text

Title: On takeoff a C402 developed maximum manifold pressure which could not be reduced and simultaneously ATC notified the pilot about a smoking engine so as he returned to land he was able to reduce power which stopped the smoking.

Narrative: Taxied out and did run up and all was normal. Cleared for takeoff and added power. Manifold Pressure (MP) came up and on rotation MP continued to climb and max out. I reduced the power in attempt to reduce MP but no reduction. As I climbed out ATC notified us of smoke out of the left engine so I immediately took control of the aircraft and began a rerun to landing. As I reduced power MP dropped down to normal and the smoke stopped so I continued with a normal landing and taxied back to the gate and deplaned the passengers. No other incidents occurred.

Data retrieved from NASA's ASRS site as of July 2013 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.