Just for you Chuck
From the POH, Beechcraft Baron 58
"Section IV (Normal Procedures)
BEFORE TAKEOFF
3. Aux Fuel Pumps - OFF (if ambient temperature is 90f or above, use LOW pressure boost)
NOTE
In high ambient temperatures, low pressure boost may be used may be required to prevent excessive fuel flow fluctuations.
BEFORE LANDING
3. Aux fuel pumps - OFF, OR LOW AS PER AMBIENT TEMPERATURE
(Books capitals, not mine)
Section VII, (Systems Description)
AUXILIARY FUEL PUMPS
An individual two-speed electric auxiliary fuel pump is provided for each engine. HIGH pressure, OFF or LOW pressure is selected with each auxiliary fuel pump swith on the pilot's subpanel. High pressure is used for providing fuel pressure before starting, and provides near maximum engine performance, should the engine driven fuel pump fail. Low pressure may be used in any operating mode to eliminate pressure fluctuations resulting from high ambient temperatures and/or high altitudes. The high pressure position should not be selected while the engine is operating except in the event of engine-driven pump failure since the high pressure mode supplies a greater pressure than can be accepted by the injection system during normal operation."
Should conclude the subject?
