0334353 JOHNSON GASKET, Idle channel

Probable Causes
Diagnostic codes
Fuel pump calibration
Fuel supply
Fuel system cleaning required
Throttle position sensor
CAN data link
High-pressure fuel pump SCV
High-pressure fuel pump
Low compression (cylinder pressure)
Electronic unit injectors
Individual malfunctioning cylinderRecommended Actions
Note: The procedures have been listed in order of probability. Complete the procedures in order.
Table 1
Troubleshooting Test Steps Values Results
1. Diagnostic Codes
A. Establish communication between the electronic service tool and the Electronic Control Module (ECM). Refer to Troubleshooting, "Electronic Service Tools", if necessary.
B. Download the Product Status Report before troubleshooting or clearing any diagnostic codes.
Note: The downloaded information will be required by the DSN if troubleshooting assistance is needed.
C. Use the electronic service tool to check for active or logged codes.
Codes
Result: There are active codes.
Repair: Troubleshoot any active codes before continuing with this procedure.
Result: There are no active codes.
Proceed to Test Step 2.
2. Fuel Pump Calibration
A. Establish communication between the electronic service tool and the Electronic Control Module (ECM). Refer to Troubleshooting, "Electronic Service Tools", if necessary.
B. Perform the "Fuel Pump Learn" procedure.
Fuel pump calibration
Result: The symptom is eliminated.
Repair: Return the unit to service.
Result: The symptom is still present.
Proceed to Test Step 2.
3. Fuel Supply
A. Visually check the fuel tank for fuel. The fuel gauge may be faulty.
B. Ensure that the vent in the fuel cap is not filled with debris.
C. Ensure that the fuel supply valve (if equipped) is in the full OPEN position.
D. Check the filter/water separator for water in the fuel.
E. Check for fuel supply lines that are restricted.
F. Check that the Electric Fuel Lift Pump (EFLP) is operating. If the EFLP is suspect, refer to Troubleshooting, "Relay - Test (Electric Fuel Lift Pump)".
G. Check for air in the fuel system. Refer to Systems Operation, Testing, and Adjusting, "Air in Fuel - Test".
H. Obtain a fuel analysis to confirm that the correct fuel is being used. Refer to Systems Operation/Testing and Adjusting, "Fuel Quality - Test" for the correct procedure.
Fuel supply
Result: There is air in the fuel system.
Repair: Prime the fuel system. Refer to Systems Operation, Testing, and Adjusting, "Fuel System - Prime".
Result: The fuel quality is not OK.
Repair: Replace the fuel. Replace the in-line fuel filter that is upstream of the EFLP. Replace the primary and secondary fuel filters. Verify that the repair eliminated the fault.
Result: The fuel quality is OK.
Proceed to Test Step 4.
4. Clean the Fuel System
A. Following the instructions on the bottle, add Caterpillar Fuel System Cleaner 343-6210 to the fuel tank.
Electronic Unit Injectors
Result: Performance should be restored within 2-3 hours.
Return the unit to service, the fuel system will be cleaned during operation.
Result: Performance is not restored within 2-3 hours.
Proceed to Test Step 5.
5. Throttle Position Sensor
Note: This Test Step is only applicable if the machine has a hand or foot throttle.
A. Use the electronic service tool and observe the signal for the throttle position sensor. Make sure that the throttle response is smooth and progressive.
Throttle
Result: The throttle position sensor response is erratic.
Repair: Test the throttle position sensor. Refer to Troubleshooting, "Speed Control (Analog) - Test". Verify that any repair eliminated the fault.
Result: The throttle position sensor response is OK.
Proceed to Test Step 6.
6. Check the CAN Data Link
Note: This Test Step is only applicable if the desired engine speed signal is sent through the CAN data link.
A. Use the electronic service tool to check for diagnostic codes that are related to the CAN data link.
Throttle
Result: The CAN data link is suspect.
Repair: Test the CAN data link. Refer to Troubleshooting, "CAN Data Link - Test". Verify that any repair eliminated the fault.
Result: The CAN data link is OK.
Proceed to Test Step 7.
7. High-Pressure Fuel Pump SCV
A. Use the electronic service tool to perform a solenoid test on the high-pressure fuel pump. Refer to Troubleshooting, "Solenoid Valve - Test".
High-pressure fuel pump
Result: The solenoid valve test fails.
Repair: Replace the high-pressure fuel pump assembly. Proceed to Test Step 8.
Result: The solenoid valve test passes successfully.
Proceed to Test Step 8.
8. High-Pressure Fuel Pump
Note: The high-pressure fuel pump that is installed by the factory is a nonserviceable item. If any fault occurs within the high-pressure fuel pump, the pump must be replaced.
A. Use the electronic service tool to select the correct screen to display any diagnostic trouble codes that relate to the high-pressure fuel pump.
High-pressure fuel pump
Result: There are diagnostic codes associated with the high-pressure fuel pump.
Repair: Diagnose the codes. Refer to Troubleshooting, "Diagnostic Trouble Code".
If necessary, replace the high-pressure fuel pump.
Result: The high-pressure fuel pump is OK.
Proceed to Test Step 9.
9. Low Compression (Cylinder Pressure)
A. Perform a compression test. Refer to Systems Operation, Testing, and Adjusting, "Compression - Test".
Cylinder compression
Result: The results of the compression test are outside the specifications.
Repair: Investigate the cause and rectify any faults.
Note: Possible causes of low compression are shown in the following list:
Loose glow plugs
Faulty piston
Faulty piston rings
Worn cylinder bores
Worn valves
Faulty cylinder head gasket
Damaged cylinder head
Result: The results of the compression test are OK.
Proceed to Test Step 10.
10. Electronic Unit Injectors
A. Use the electronic service tool to perform the automatic "Cylinder Cut Out Test".
Note: If the compression test that was performed in Test Step 8 was satisfactory, the "Cylinder Cut Out Test" will identify any faulty injectors.
Electronic Unit Injectors
Result: A faulty electronic unit injector is indicated.
Repair: Remove any faulty electronic unit injectors. Refer to Disassembly and Assembly, "Electronic Unit Injector - Remove".
Install new electronic unit injectors. Refer to Disassembly and Assembly, "Electronic Unit Injector - Install".
Repeat the automatic "Cylinder Cut Out Test". If the fault is still apparent, remove the replacement electronic unit injector and install the original electronic unit injector. Refer to Disassembly and Assembly, "Electronic Unit Injector - Remove" and Disassembly and Assembly, "Electronic Unit Injector - Install".
Result: All injectors are OK.
Proceed to Test Step 11.
11. Individual Malfunctioning Cylinders
A. With the engine speed at a fast idle, use the electronic service tool to perform the manual "Cylinder Cut Out Test".
As each cylinder is cut out, listen for a change in the sound from the engine. When a cylinder is cut out, there should be a noticeable change in the sound of the engine.
If a change in the sound of the engine is not