Troubleshooting

54 RENR2696-01
Troubleshooting Section
Valve Lash
1. Ensure that the valve lash is correct. Refer to
Testing and Adjusting, “Engine Valve Lash -
Inspect/Adju
st”. Rest the valve lash if it is not
correct.
2. If the repair d
oes not eliminate the fault proceed to
“Low Compression (cylinder pressure)”.
Low Compressi
on (cylinder pressure)
1. Remove the fuel injection nozzles and perform a
compression
test. Refer to Systems Operation,
Testing and Adjusting, “Compression - Test ”data.
2. Make all nece
ssary repairs to the engine.
3. Ensure that the repairs have eliminated the faults.
Examples of low compression are shown in the
following list:
•
Mechanical problem
•
Faulty pisto
n rings
•
Worn cylinder bores
•
Worn valves
•
Faulty cylin
der head gasket
•
Damaged cylinder head
4. If the repair does not eliminate the fault proceed
to “Air Inlet Heater Starting Aid”.
Air Inlet Heater Starting Aid
1. Verify that
the air inlet heater is operating correctly.
Refer to Testing and Adjusting, “Air Inlet Heater
-Test”.
2. If the repair does not eliminate the fault proceed to
“Fuel Injection Nozzles”.
Fuel Injection Nozzles
1. Remove the
fuel injection nozzles from the cylinder
head. Refer to Disassembly and Assembly, “Fuel
InjectionNozzle-Remove”.
2. Check the fuel injection nozzles. Refer to Testing
and Adjusting, “Fuel Injection Nozzle - Test”.
3. Ensure that the repairs have eliminated the
problems.
4. If the problem has not been eliminated, proceed
to “Coolant Tem
perature Sensor Circuit”.
Coolant Temperature Sensor Circuit
1. Connect the electronic service tool to the
diagnostic connector.
2. Monitor the display screen on the electronic
service tool in order to verify the presence of active
diagnostic co
des for the coolant temperature.
Refer to Troubleshooting, “Engine Temperature
Sensor Open or Short Circuit - Test”.
Engine Pressure Sensors
1. Connect the e
lectronic service tool to the
diagnostic connector.
2. Monitor the d
isplay screen on the electronic
service tool in order to verify the presence of
active diagnostic codes for the engine pressure
sensors. Re
fer to Troubleshooting, “5 Volt Engine
Pressure Sensor Supply Circuit - Test”.
i01798131
Intake Air Temperature Is Too
High
Probable Causes
•
High ambient air temperature
•
High coolant temperature
•
High intake air restriction and/or high altitude
•
Faulty intake manifold air temperature sensor
and/or circuit
•
Insufficient flow of cooling water through the
aftercooler (if equipped)
•
Insufficient flow of air through the aftercooler (if
equipped)
Recommended Repairs
High Am bient Air Temperature
Determine if the ambient air temperature is within the
design specifications for the cooling system.
Determine the cause of the high air temperature.
Make corrections, when possible.