PCM 2007 5.0L MPI Owner's Operation And Maintenance Manual page 66

TROUBLESHOOTING - 14
Malfunction
Engine Overheats
The following applies to engines
equipped with Fresh-Water
Cooling (FWC) systems.
Insuffi cient engine temperature
Engine oil pressure low
64
Possible Cause
Loose or worn drive belt(s)
Collapsed, kinked or leaking
hoses.
Transmission/engine oil cooler
plugged
Faulty thermostat
Sea-water intake valve
partially/fully closed.
Restricted sea-water pickup
Faulty temperature sending unit
or gauge
Sea-water pump impeller worn or
damaged
Coolant level low in the fresh-water
section of the cooling system
Heat exchanger passages plugged
with scales and debris
Improper coolant mixture
Faulty thermostat
Faulty temperature sender
Faulty oil pressure sending unit
or gauge
Oil level low
Crankcase overfi lled causing oil
aeration
Diluted or improper grade/
viscosity of oil
L510010-07A
Corrective Action
Adjust or replace the belts as
necessary.
Replace the hoses.
Remove the water hoses and fl ush
in opposite direction of the normal
fl ow.
Replace the thermostat.
Open the valve completely.
Remove restriction.
Test and replace as necessary.
Replace the impeller.
Check the cooling system for leaks.
Refi ll the system. See Warning
before removing the fi ll cap.
Clean and fl ush the exchanger.
Install the proper coolant mixture
(50% antifreeze - 50% water).
Replace the thermostat.
Replace the temperature sender.
Test and replace as necessary.
Add specifi ed oil. Check the engine
for leaks.
Remove the required amount of oil.
Determine the cause of overfi lled
condition (improper fi lling, etc.).
Change the oil and fi lter.
Determine the cause of dilution.
(insuffi cient engine temperature,
excessive idling, etc.)