Hummer H2. Manual - part 1462

2. For US dealers, empty 2 pre-measured GM Top-Engine Cleaner containers, 24 ml (0.812 oz) each, GM 

P/N 12346535, into the J 35800-A .  

3. For Canadian dealers, measure and dispense 48 ml (1.62 oz) of Top-Engine Cleaner, Canadian P/N 

992872, into the J 35800-A .  

4. If you are using any other brand of tank you will need a total of 96 ml (3.24 oz) of Top-Engine Cleaner 

mixed with 864 ml (29.16 oz) of regular unleaded gasoline.  

5. Fill the injector cleaning tank with regular unleaded gasoline. Be sure to follow all additional instructions 

provided with the tool.  

6. Electrically disable the vehicle fuel pump by removing the fuel pump relay and disconnecting the oil 

pressure switch connector, if equipped.  

7. Disconnect the fuel feed and return line, if equipped, at the fuel rail. Plug the fuel feed and return line, if 

equipped, coming off the fuel rail with J 37287 , or J 42964-1 , and J 42964-2 or J 42873-1 , and J 42873-
2 as appropriate for the fuel system. See Special Tools and Equipment .  

8. Connect the J 35800-A to the vehicle fuel rail.  

9. Pressurize the J 35800-A to 510 kPa (75 psi).  

10. Start and idle the engine until it stalls due to lack of fuel. This should take approximately 15-20 minutes.  

11. Disconnect J 35800-A from the fuel rail.  

12. Reconnect the vehicle fuel pump relay and oil pressure switch connector, if equipped.  

13. Remove J 37287 or J 42964-1 , and J 42964-2 or J 42873-1 , and J 42873-2 and reconnect the vehicle 

fuel feed and return lines. See Special Tools and Equipment .  

14. Start and idle the vehicle for an additional 2 minutes to ensure residual injector cleaner is flushed from the 

fuel rail and fuel lines.  

15. Repeat steps 1-5 of the Injector Balance Test, and record the fuel pressure drop from each injector.  

16. Subtract the lowest fuel pressure drop from the highest fuel pressure drop. If the value is 15 kPa (2 psi) or 

less, no additional action is required. If the value is greater than 15 kPa (2 psi), replace the injector with 
the lowest fuel pressure drop.  

17. Add one ounce of Port Fuel Injector Cleaner, GM P/N 12345104 (Canadian P/N 10953467), to the 

vehicle fuel tank for each gallon of gasoline estimated to be in the fuel tank. Instruct the customer to add 
the reminder of the bottle of Port Fuel Injector Cleaner to the vehicle fuel tank at the next fill-up.  

18. Advise the customer to change brands of fuel and to add GM Port Fuel Injector Cleaner every 5 000 km 

(3,000 mi). GM Port Fuel Injector Cleaner contains the same additives that the fuel companies are 
removing from the fuel to reduce costs. Regular use of GM Port Fuel Injector Cleaner should keep the 
customer from having to repeat the injector cleaning procedure.  

19. Road test the vehicle to verify that the customer concern has been corrected.  

EVAPORATIVE EMISSION (EVAP) CANISTER PURGE SOLENOID VALVE REPLACEMENT 

Removal Procedure 

 

2004 Hummer H2 

2004 ENGINE PERFORMANCE Engine Controls (Introduction) - 4.8L, 5.3L, and 6.0L - Hummer H2

  

Fig. 129: View Of Top Engine Cover 
Courtesy of GENERAL MOTORS CORP. 

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

Mechanical. 

 

2004 Hummer H2 

2004 ENGINE PERFORMANCE Engine Controls (Introduction) - 4.8L, 5.3L, and 6.0L - Hummer H2

  

Fig. 130: Pushing Evaporative Emission (EVAP) Pipe Quick Connect Fitting Retainer Inward 
Courtesy of GENERAL MOTORS CORP. 

2. Push the evaporative emission (EVAP) pipe quick connect fitting retainer inward. 

 

2004 Hummer H2 

2004 ENGINE PERFORMANCE Engine Controls (Introduction) - 4.8L, 5.3L, and 6.0L - Hummer H2

  

Fig. 131: Top View Of Engine 
Courtesy of GENERAL MOTORS CORP. 

3. Disconnect the EVAP pipe (2) from the EVAP purge solenoid (1). 

 

2004 Hummer H2 

2004 ENGINE PERFORMANCE Engine Controls (Introduction) - 4.8L, 5.3L, and 6.0L - Hummer H2