Troubleshooting

Table 13
Troubleshooting Test Steps
Values Results
1. Diagnostic Codes
A. Establish communication between the electronic service tool
and the Electronic Control Module (ECM).
B. Check for active diagnostic codes.
Codes Result: A diagnostic trouble code is active or logged.
Repair: Troubleshoot the active or logged codes. Refer to
Troubleshooting, “Diagnostic Trouble Codes”.
Result: A diagnostic trouble code is not active or logged.
Proceed to Test Step 2.
2. Fuel Quality
A. Check the fuel quality. Refer to Systems Operation, Testing, and
Adjusting, “Fuel Quality - Test”.
B. Refer to Operation and Maintenance Manual for information on
the proper characteristics of the fuel for the engine.
Fuel Result: The fuel quality is not OK.
Repair: Drain the fuel system and replace the fuel filters.
Refer to the Operation and Maintenance Manual, “Fuel
System Primary Filter (Water Separator) Element - Re-
place” and Operation and Maintenance Manual, “Fuel Sys-
tem Filter - Replace”.
Fill the fuel system with fuel that meets the standard in the
Operation and Maintenance Manual, “Fluid
Recommendations”.
Prime the fuel system. Refer to the Operation and Mainte-
nance Manual, “Fuel System - Prime”.
Verify that the procedure has eliminated the noise.
Result: The fuel quality is OK.
Proceed to Test Step 3.
3. Valve Train Components
A. Check the valve lash. Refer to Troubleshooting, “Valve Lash Is
Excessive”.
B. Check for damage to valve train components. Remove the valve
cover from the suspect cylinders. Check the following items for
damage:
· Valve springs
· Rocker shaft
· Pushrods
· Camshaft followers
Refer to the Disassembly and Assembly for additional information.
Valve train Result: Valve train components are damaged.
Repair: Make the necessary repairs, Verify that the repair
has eliminated the noise.
Result: The valve train components are not damaged.
Proceed to Test Step 4.
(continued)
46 UENR0612-07
Symptom Troubleshooting
This document has been printed from SPI2. NOT FOR RESALE