3.9 and B5.9 Series Engines
Troubleshooting Symptoms Charts
Section TS - Troubleshooting Symptoms
Engine Power Output Low (Continued)
Check the flow through the fuel filter. Replace
the fuel filter if necessary. Refer to Procedure
Fuel filter or fuel inlet restriction
006-015. Clean all prefilters and screens.
Check the fuel suction line for restriction.
Check the fuel drain lines for restriction. Clear
or replace the fuel lines, check valves, or tank
uel drain line is restricted
vents as necessary. Refer to Procedure
Inspect the fuel transfer pump. Replace if
uel transfer pump malfunctioning
necessary. Refer to Procedure 005-045.
uel pump return overflow valve is malfunction-
Inspect the return overflow valve. Replace if
necessary. Refer to Procedure 006-044.
ubricating oil level is above or below specifi-
Check the oil level. Add or drain oil, if neces-
sary. Refer to Procedure 007-043.
Inspect the air cleaner element. Replace as
needed. Refer to the OEM service manual or
lugged air filter
the Operation and Maintenance Manual, B
Series Engines, Bulletin No. 3810205.
If the vehicle is equipped with a valve switch
ntake air source is incorrect
the intake source from under the hood to
outside, position and valve for the season.
Tighten the fittings, repair plumbing, replace
wastegate diaphragm. Refer to Procedure
ir fuel tube leaking, wastegate diaphragm
010-050 or the Turbocharger Master Repair
ruptured, or wastegate plumbing damaged
Manual, Bulletin No. 3580555.