Hummer H2. Manual - part 1718

Fig. 76: Harness Clips, Main Coil Harness & Fuel Injector Electrical Connectors 
Courtesy of GENERAL MOTORS CORP. 

1. Remove the engine sight shield. Refer to Engine Sight Shield Replacement (6.0L (LQ4)) .  

2. Remove the connector position assurance (CPA) lock.  

3. Disconnect the main electrical connector (2) feeding the ignition coils.  

4. Remove the harness clips (1).  

5. Reposition the engine harness.  

6. Remove the spark plug wires from the ignition coils. 

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Twist each plug wire 1/2 turn.  

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Pull only on the boot in order to remove the wire from the ignition coil.  

 

2004 Hummer H2 

2004 ENGINE Engine Mechanical - 4.8L, 5.3L, and 6.0L - Hummer H2

  

Fig. 77: Ignition Coil & Bracket Assembly (Left) 
Courtesy of GENERAL MOTORS CORP. 

7. Remove the ignition coil bracket studs from the rocker arm cover.  

8. Remove the ignition coils and bracket from the rocker arm cover.  

9. Remove the valve rocker arm cover bolts.  

10. Remove the valve rocker arm cover. 

 

2004 Hummer H2 

2004 ENGINE Engine Mechanical - 4.8L, 5.3L, and 6.0L - Hummer H2

  

Fig. 78: Valve Rocker Arm Cover Gasket (Left) 
Courtesy of GENERAL MOTORS CORP. 

11. Remove the gasket (1) from the rocker cover.  

12. Discard the OLD gasket.  

13. Clean and inspect the rocker arm cover. Refer to Valve Rocker Arm Cover Cleaning and Inspection .  

Installation Procedure 

IMPORTANT:

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All gasket surfaces should be free of oil an/or other foreign material 
during assembly.  

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DO NOT reuse the valve rocker arm cover gasket.  

 

2004 Hummer H2 

2004 ENGINE Engine Mechanical - 4.8L, 5.3L, and 6.0L - Hummer H2

  

Fig. 79: Valve Rocker Arm Cover Gasket (Left) 
Courtesy of GENERAL MOTORS CORP. 

1. Install a NEW rocker cover gasket (1) into the valve rocker cover lip.  

2. Install the valve rocker arm cover onto the cylinder head.  

3. Install new rocker arm cover grommets, if necessary. 

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The valve rocker arm cover bolt grommets may be reused.  

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If the PCV valve grommet has been removed from the rocker cover, install 
a NEW grommet during assembly.  

NOTE:

Refer to Fastener Notice in Cautions and Notices.

 

2004 Hummer H2 

2004 ENGINE Engine Mechanical - 4.8L, 5.3L, and 6.0L - Hummer H2