Perkins M250C - Engine Misfires, Runs Rough or Is Unstable

48 KENR9126
Troubleshooting Section
2. Check the diesel fuel for contamination.
Low Oil Pressure
Refer to Troub
leshooting, “Low Engine Oil Pressure”
for the testing procedure. Repair any identified faults.
i04010450
Engine Misfires, Runs Rough
or Is Un stab le
Note: If the fault is intermittent and the fault cannot
be duplicated, refer to Troubleshooting, “Intermittent
Low Power or Power Cutout”.
Note: If the fault only occurs under certain conditions,
test the engine under those conditions. Examples
of certain conditions are high rpm, full load, and
engine operating temperature. Troubleshooting
the symptoms under other conditions can give
misleading results.
The probable root causes are listed in order below:
Probable Causes
•
Diagnostic codes
•
Throttlepositionsensor
•
Air intake and exhaust system
•
Fuel supply
•
Fuel rail pump
•
Low compression (cylinder pressure)
•
Individual malfunct ioning cylinder
•
Electronic unit injectors
Recommended Actions
Diagnostic Codes
Check for active diagnostic codes on the electronic
service tool. T roubleshoot any active codes before
continuing with this procedure.
Throttle Position Sensor
1. Use the electronic service tool and observe the
signal for the throttle position sensor. The status
should be 0 percent at low idle and the status
should be 100 percent at high idle.
2. If the signal is erratic, refer to Troubleshooting,
“Digital Throt
tle Position Sensor Circuit - Test”.
3. If the repairs do not eliminate the fault proceed to
“Air Intake an
d Exhaust System”.
Air Intake and Exhaust System
1. Check the air filter restriction indicator, if equipped.
2. Ensure that
the air filter is clean and serviceable.
3. Check the air intake and exhaust systems for the
following d
efects:
•
Blockages
•
Restrictions
•
Damage to l
ines or hoses
4. If the repairs do not eliminate the fault proceed to
“Fuel Sup
ply”.
Fuel Supply
1. Visually check the fuel tank for fuel. The fuel
gauge may be faulty.
2. Ensure that the fuel supply valve (if equipped) is
in the full OPEN position.
3. If the temperature is below 0 °C (32 °F), check
for solidified fuel (wax).
4. Check the primary filter/water separator for water
in the fuel.
5. Check for fuel supply lines that are restricted.
6. Check
that the low-pressure fuel lines are tight
and secured properly.
7. Chec
kthefuelfilters.
8. Check the diesel fuel for contamination.
9. Check for air in the fuel system.
10. Ens
ure that the fuel system has been primed.
11. Check the fuel pressure.
12. If the repair does not eliminate the fault refer to
“FuelRailPump”.
Fuel Rail Pump
No
te: The fuel rail pump that is installed by the
factory is a nonserviceable item. If any mechanical
fault or any electrical fault occurs within the fuel rail
p
ump then the fuel rail pump must be replaced.