* Defect In Unit Injector Sleeve
1. Defect in unit injector sleeve:
Remove unit injectors and inspect sleeves in cylinder head unit injector bores. Look for signs of cavitation erosion or cracks. Cavitation on the inside may be due to air bubbles in the fuel. Air bubbles may be due to a leak on the suction side of the fuel transfer pump, or they may be caused by combustion leakage. Check for pathways or cracks at the unit injector/sleeve interference fit near the unit injector nozzle. If cavitation erosion is found on the outside of the sleeve after removal of the sleeve from the cylinder head, it may be due to an incorrect level of coolant conditioner. If any problems are seen, remove the sleeve(s) and replace with new parts.
NOTE: Refer to Disassembly And Assembly, SENR6553, for the proper procedure for unit injector removal and installation.