A C207 PLT HAD AN ENG FAILURE ON LNDG AT GCN.

Narrative

STARTING THE ACFT WAS NORMAL. ENG IDLED SMOOTHLY. ENG THEN STARTED TO DIE. I ADDED PWR THINKING THAT THE ENG WAS VAPOR LOCKING AND UPON REDUCTION OF PWR; RESUMED SMOOTH OP. ALL FLT CHARACTERISTICS REMAINED NORMAL FOR THE FIRST 1/2 OF THE FLT. THE MANIFOLD PRESSURE BEGAN OSCILLATING BTWN 29 INCHES AND 15 INCHES OF PRESSURE. TIME BTWN OSCILLATIONS WAS APPROX 2-3 SECONDS BTWN HIGH AND LOW PEAKS. THE FUEL FLOW INDICATED 4 GPH; ACTIVATION OF THE EMER FUEL PUMPS INCREASED MANIFOLD PRESSURE TO OSCILLATIONS BTWN 36 INCHES AND 15 INCHES. I TOOK THE OPPORTUNITY TO SWITCH FUEL TANKS. I THROTTLED BACK TO IDLE TO TURN FINAL. HOWEVER; BEING HIGH AND OVER THE NUMBERS I DECIDED TO MAKE A SINGLE 270-360 DEG TURN TO THE RWY TO LOSE SOME ALT. WHEN I BEGAN MY TURN I ADDED PWR SO AS NOT TO LOSE TOO MUCH ALT IN THE TURN. HOWEVER; NOTHING HAPPENED WHEN I ADVANCED THE THROTTLE. SO I AMENDED MY 270-360 DEG TURN TO ABOUT AN 85 DEG TURN AND LANDED LONG AS PLANNED. I FEEL THAT THE EVENTS THAT OCCURRED WERE MECHANICAL IN NATURE. THE QUESTION OF FUEL STARVATION HAS ALSO RISEN. THE L TANK WAS DRY UPON LNDG; ALTHOUGH THE R TANK WAS THE TANK IN USE AT THE TIME OF COMPLETE ENG FAILURE.