H3 2006

Secondary Air Injection System

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Secondary Air Injection Check Valve



Location

Specific to:

Hummer H3 2006-2010

The AIR check valve is located above the exhaust manifold.

Operation

Specific to:

Hummer H3 2006-2010

The Secondary Air Injection (AIR) system aids in the reduction of hydrocarbon exhaust emissions during a cold start-up. This occurs when the start-up Engine Coolant Temperature (ECT) is between 41-122°F (5-50°C), and the Intake Air Temperature (IAT) is between 41-140°F (5-60°C). The AIR pump operates 5-60 seconds after start-up.

The Engine Control Module (ECM) activates the AIR system by simultaneously supplying grounds to the AIR pump and the AIR valve relays. This action closes the relays' internal contacts. The AIR pump and the AIR control solenoid valve/pressure sensor assembly are in turn energized, the pump runs and the control/shut-off valve opens.

The AIR pump sends pressurized fresh air into the pipes/hoses through the open control/shut-off valve, and into the exhaust manifold. The extra air accelerates the catalyst operation, helping it to reach operating temperature faster. The AIR pump remains ON for a short period of time after the control/shut-off valve is commanded OFF. When the AIR pump is commanded OFF it will not run or be activated until the next vehicle start. When the AIR system is inactive, the closed AIR control/shut-off valve prevents air/exhaust flow in either direction.

The AIR system pressure sensor is used to monitor pressure at the AIR control solenoid valve/pressure sensor assembly inlet during the commanded ON/OFF states.

The AIR system includes the following components:



The AIR pump-The electric AIR pump supplies pressurized, filtered air to the AIR control/shut-off valve. The AIR pump is a turbine type pump that is permanently lubricated and requires no periodic maintenance.
 


NOTE
The AIR solenoid, control/shut-off valve, and the pressure sensor are serviced as an assembly.



The AIR solenoid-The AIR solenoids opens the AIR control/shut-off valve when the solenoid is energized by the AIR solenoid relay.
 


NOTE
An audible exhaust or fluttering noise may be heard at the control solenoid valve/pressure sensor assembly inlet when the valve is open and the AIR hose is removed from the control solenoid valve/pressure sensor assembly.



The AIR control solenoid valve/pressure sensor assembly-The AIR control solenoid valve/pressure sensor assembly has a solenoid mounted valve. When the valve is open by the solenoid, pressurized air from the AIR pump flows through the control solenoid valve/pressure sensor assembly and is directed into the exhaust manifold through an outlet pipe.
 
The AIR pressure sensor-The AIR pressure sensor is a part of the AIR control solenoid valve/pressure sensor assembly. The sensor is a 3-wire sensor that measures the AIR system pressure at the AIR control solenoid valve/pressure sensor assembly inlet.
 
The AIR pump relay-The AIR pump relay supplies high current and battery voltage to the AIR pump. The ECM commands the relay ON by supplying a ground to the relay control circuit.
 
The AIR valve relay-The AIR valve relay supplies high current and battery voltage to the AIR solenoid. the ECM commands the relay ON by supplying a ground to the relay control circuit.
 
The pipes and hoses-The AIR system hose carries filtered air from the engine air cleaner to the AIR pump inlet. The pipe/hoses carry the air from the AIR pump to the AIR control solenoid valve/pressure sensor assembly and on to the exhaust manifold.
 
The inlet filter-The AIR system does not have a separate inlet air filter. Filtered air is drawn from the engine air cleaner assembly.
 

Removal & Installation

Specific to:

Hummer H3 2006-2010

  1. Open the hood.
  2.  
  3. Remove the air cleaner outlet duct.
  4.  
  5. Disconnect the Secondary Air Injection (AIR) pump outlet hose quick connect fitting from the AIR check valve.

    Click image to see an enlarged view

    Fig. Disconnect the Secondary Air Injection (AIR) pump outlet hose quick connect fitting from the AIR check valve

  6.  
  7. Disconnect the engine wiring harness electrical connector from the AIR check valve.

    Click image to see an enlarged view

    Fig. Disconnect the engine wiring harness electrical connector (1) from the AIR check valve

  8.  
  9. Remove the AIR check valve studs.

    Click image to see an enlarged view

    Fig. Remove the AIR check valve studs (3), the AIR check valve (2) and gasket (1)

  10.  
  11. Remove the AIR check valve and gasket. Discard the gasket.
  12.  

To install:

  1. Place a NEW AIR check valve gasket between the engine and the valve.
  2.  
  3. Position the AIR check valve to the engine.
  4.  
  5. Install the AIR check valve studs. Tighten to studs to 18 ft. lbs. (25 Nm).
  6.  
  7. Connect the engine wiring harness electrical connector to the AIR check valve.
  8.  
  9. Connect the AIR pump outlet hose quick connect fitting to the AIR check valve.
  10.  
  11. Install the air cleaner outlet duct.
  12.  
  13. Close the hood.
  14.  

Testing

Specific to:

Hummer H3 2006-2010



Click image to see an enlarged view

Fig. Related Diagnostic Trouble Codes

Secondary Air Injection Pump



Location

Specific to:

Hummer H3 2006-2010

The AIR pump is located at the right front of the engine compartment mounted to the vehicle frame.

Operation

Specific to:

Hummer H3 2006-2010

The Secondary Air Injection (AIR) system aids in the reduction of hydrocarbon exhaust emissions during a cold start-up. This occurs when the start-up Engine Coolant Temperature (ECT) is between 41-122°F (5-50°C), and the Intake Air Temperature (IAT) is between 41-140°F (5-60°C). The AIR pump operates 5-60 seconds after start-up.

The Engine Control Module (ECM) activates the AIR system by simultaneously supplying grounds to the AIR pump and the AIR valve relays. This action closes the relays' internal contacts. The AIR pump and the AIR control solenoid valve/pressure sensor assembly are in turn energized, the pump runs and the control/shut-off valve opens.

The AIR pump sends pressurized fresh air into the pipes/hoses through the open control/shut-off valve, and into the exhaust manifold. The extra air accelerates the catalyst operation, helping it to reach operating temperature faster. The AIR pump remains ON for a short period of time after the control/shut-off valve is commanded OFF. When the AIR pump is commanded OFF it will not run or be activated until the next vehicle start. When the AIR system is inactive, the closed AIR control/shut-off valve prevents air/exhaust flow in either direction.

The AIR system pressure sensor is used to monitor pressure at the AIR control solenoid valve/pressure sensor assembly inlet during the commanded ON/OFF states.

The AIR system includes the following components:



The AIR pump-The electric AIR pump supplies pressurized, filtered air to the AIR control/shut-off valve. The AIR pump is a turbine type pump that is permanently lubricated and requires no periodic maintenance.
 


NOTE
The AIR solenoid, control/shut-off valve, and the pressure sensor are serviced as an assembly.



The AIR solenoid-The AIR solenoids opens the AIR control/shut-off valve when the solenoid is energized by the AIR solenoid relay.
 


NOTE
An audible exhaust or fluttering noise may be heard at the control solenoid valve/pressure sensor assembly inlet when the valve is open and the AIR hose is removed from the control solenoid valve/pressure sensor assembly.



The AIR control solenoid valve/pressure sensor assembly-The AIR control solenoid valve/pressure sensor assembly has a solenoid mounted valve. When the valve is open by the solenoid, pressurized air from the AIR pump flows through the control solenoid valve/pressure sensor assembly and is directed into the exhaust manifold through an outlet pipe.
 
The AIR pressure sensor-The AIR pressure sensor is a part of the AIR control solenoid valve/pressure sensor assembly. The sensor is a 3-wire sensor that measures the AIR system pressure at the AIR control solenoid valve/pressure sensor assembly inlet.
 
The AIR pump relay-The AIR pump relay supplies high current and battery voltage to the AIR pump. The ECM commands the relay ON by supplying a ground to the relay control circuit.
 
The AIR valve relay-The AIR valve relay supplies high current and battery voltage to the AIR solenoid. the ECM commands the relay ON by supplying a ground to the relay control circuit.
 
The pipes and hoses-The AIR system hose carries filtered air from the engine air cleaner to the AIR pump inlet. The pipe/hoses carry the air from the AIR pump to the AIR control solenoid valve/pressure sensor assembly and on to the exhaust manifold.
 
The inlet filter-The AIR system does not have a separate inlet air filter. Filtered air is drawn from the engine air cleaner assembly.
 

Removal & Installation

Specific to:

Hummer H3 2006-2010

  1. Open the hood.
  2.  
  3. From under the hood, disconnect the Secondary Air Injection (AIR) pump inlet hose quick connect fitting from the pump.

    Click image to see an enlarged view

    Fig. Disconnect the AIR pump inlet (1) and outlet (2) hoses from the pump

  4.  
  5. Disconnect the AIR pump outlet hose quick connect fitting from the pump.
  6.  
  7. Remove the engine shield.
  8.  
  9. Disconnect the engine wiring harness electrical connector from the AIR pump wiring harness electrical connector.

    Click image to see an enlarged view

    Fig. Disconnect the engine wiring harness electrical connector from the AIR pump wiring harness electrical connector

  10.  
  11. Squeeze the AIR pump wiring harness electrical connector clip together and push up in order to separate the clip/connector from the bracket.

    Click image to see an enlarged view

    Fig. Separate the AIR pump wiring harness electrical connector clip (1) from the bracket; open the wiring harness clip (2) and remove the harness from the clip

  12.  
  13. Open the AIR pump wiring harness clip and remove the harness from the clip.
  14.  
  15. Remove the AIR pump nuts.

    Click image to see an enlarged view

    Fig. Remove the AIR pump nuts (1)

  16.  
  17. Lower the vehicle.
  18.  
  19. Reposition the AIR pump inlet and outlet hoses as necessary in order to remove the pump.
  20.  
  21. Remove the AIR pump.
  22.  

To install:

  1. Install the AIR pump.
  2.  
  3. Raise and suitably support the vehicle.
  4.  
  5. Install the AIR pump nuts. Tighten the nuts to 80 inch lbs. (9 Nm).
  6.  
  7. Install the AIR pump wiring harness electrical connector clip to the bracket.
  8.  
  9. Install the AIR pump wiring harness to the clip and close the clip.
  10.  
  11. Connect the engine wiring harness electrical connector to the AIR pump wiring harness electrical connector.
  12.  
  13. Install the engine shield.
  14.  
  15. Position the AIR pump inlet and outlet hoses as necessary.
  16.  
  17. Connect the AIR pump outlet hose quick connect fitting to the pump.
  18.  
  19. Connect the AIR pump inlet hose quick connect fitting to the pump.
  20.  
  21. Close the hood.
  22.  

Testing

Specific to:

Hummer H3 2006-2010



Click image to see an enlarged view

Fig. Related Diagnostic Trouble Codes

 
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