91304-ZV5-821 Honda O-RING (Honda Code 4594818).

This service procedure requires the valve cover to be removed. This will expose the service technician to to moving parts which may case pinch or entanglement hazards. The hazards could result in personal injury or death. Keep all body parts, loose clothing, hair, and other items which could become entangled away from the moving parts.
Be sure the engine cannot be started while this maintenance is being performed. To prevent possible injury, do not use the starting motor to turn the flywheel.Hot engine components can cause burns. Allow additional time for the engine to cool before measuring/adjusting the unit injectors.The electronic unit injectors use high voltage. Disconnect the unit injector enable circuit connector in order to prevent personal injury. Do not come in contact with the injector terminals while the engine is running.
Specifications
Table 1
Torque Specifications
Location Torque
Bolt that holds the unit injector in place 55 10 N m (41 7 lb ft) Introduction
This procedure assists in identifying the cause for an injector misfiring. Perform this procedure only after performing the Cylinder Cutout Test. Refer to Troubleshooting for more information.References
Reference: Testing and Adjusting, "Air in Fuel - Test"Reference: Troubleshooting, "Electrical Connectors - Inspect"Reference: Testing and Adjusting, "Engine Valve Lash - Inspect/Adjust"Reference: Disassembly and Assembly Manual, "Electronic Unit Injector - Remove"Reference: Disassembly and Assembly Manual, "Electronic Unit Injector - Install"Reference: Testing and Adjusting, "Fuel Quality - Test"Reference: Disassembly and Assembly Manual, "Electronic Unit Injector Sleeve - Install"Required Tools
Typical Hand Tools
Table 2
Required Tools
Item Qty Part Number Part Name
T1 1 458-3562 Tool As Test Preparation
Remove the pertinent covers to expose the electronic unit injectors.Test Procedures
Check for air in the fuel, if this procedure has not already been performed. Refer to Testing and Adjusting, "Air in Fuel - Test".
Remove the valve cover and look for broken parts. Repair any broken parts or replace any broken parts that are found. Inspect all wiring to the solenoids. Look for loose connections. Also look for frayed wires or broken wires. Ensure that the connector for the unit injector solenoid is properly connected. Perform a pull test on each of the wires. Refer to Troubleshooting, "Electrical Connectors - Inspect".
Check the valve lash setting for the cylinder of the suspect unit injector. Refer to Testing and Adjusting, "Engine Valve Lash - Inspect/Adjust".
Ensure that the bolt that holds the unit injector is tightened to the proper torque. If necessary, loosen the bolt that holds the unit injector and tighten the bolt to a torque of 55 10 N m (41 7 lb ft).
Remove the suspect unit injector and check the unit injector for signs of exposure to coolant. Refer to Disassembly and Assembly Manual, "Electronic Unit Injector - Remove". Exposure to coolant will cause rust to form on the injector. If the unit injector shows signs of exposure to coolant, remove the injector sleeve and inspect the injector sleeve. Refer to Disassembly and Assembly Manual, "Electronic Unit Injector Sleeve - Remove". Replace the injector sleeve if the injector sleeve is damaged. Check the unit injector for an excessive brown discoloration that extends beyond the injector tip. If excessive discoloration is found, check the quality of the fuel. Refer to Testing and Adjusting, "Fuel Quality - Test". Replace the seals on the injector and reinstall the injector. Refer to Disassembly and Assembly Manual, "Electronic Unit Injector - Install". Also refer to Disassembly and Assembly Manual, "Electronic Unit Injector Sleeve - Install".
If the problem is not resolved, replace the suspect injector with a new injector.Disconnecting and Connecting the Injector Harness
Use care when performing any engine service procedure that requires disconnecting the injector harness from the injectors. This helps to prevent future injector and/or injector harness connector failures
Note: Do not pull on the harness wires in order to remove the connector from the injector.Note: Do not apply excessive force to the connector body during removal.
When injector faults are present, carefully inspect the injector connector pins for arcing. Replace the suspect injector, and injector harness assembly when evidence of pin arcing is present.Note: Do not use socket connector repair kits at injector connections on engines utilizing this over-molded design. Wire length is critical in order to avoid contact with other components.
Ensure that the injector harness connector is fully engaged until the locking tab clicks into place.
Use 458-3562 Tool As to aid with disconnecting and connecting the injector harness connectors.
Note the location of the 458-3562 Tool As on the connector body when disconnecting and connecting the harness. The stop pin in the 458-3562 Tool As will prevent crushing the connector and reduce the chance for damage to wiring.
Illustration 1 g03715990
(2) 11mm Opening Minimum
(3) 9.5mm Diameter Stop
(4) Removal With 458-3562 Tool As
(5) Installation With 458-3562 Tool As
(6) 279 mm (11 inch) Pliers With 45 Degree Offset