Removal Procedure
Important: The intake manifold, throttle body, fuel
rail, and injectors may be  removed as an assembly. If not servicing the individual
components, remove  the manifold as a complete assembly.
- Remove the throttle body. Refer to   
Throttle Body Assembly Replacement 
  in Engine Controls - 4.8L, 5.3L, and  6.0L.
 
- Remove the oil fill tube. Refer to 
Oil Level Indicator and Tube Replacement 
.
 
- Remove the fuel injectors. Refer to   
Fuel Injector Replacement 
  in Engine Controls - 4.8L, 5.3L, and  6.0L.
 
- Disconnect the following  electrical connectors:
 
| •  | Manifold absolute pressure (MAP) sensor (1) | 
 
| •  | Exhaust gas recirculation (EGR) valve, if equipped | 
 
- Remove the knock sensor harness electrical connector from the  intake
manifold.
 
- Set the electrical harness aside.
 
- If equipped, remove the  following EGR pipe
bolts:
 
- If equipped, remove the EGR pipe (with valve).
 
- If equipped, remove the EGR pipe gasket from the exhaust manifold.
 
- Remove the positive crankcase  ventilation
(PCV) hose (with valve).
 
- Remove the MAP sensor  (1) from the intake
manifold.
 
- Remove the accelerator control cable bracket
bolts (1).
 
- Remove the accelerator control cable bracket (2) from the intake  manifold.
 
- Remove the evaporative  emission (EVAP)
purge solenoid vent tube by performing the following:
 
| 14.1.  | Remove the EVAP tube end (2) from the solenoid (1). | 
 
| 14.2.  | Squeeze the EVAP pipe quick connect fitting (3) retainer together. | 
 
| 14.3.  | Remove the EVAP tube end (3) from the vapor pipe. | 
 
- Remove the EVAP purge  solenoid bolt (2),
solenoid (3), and isolator (1) from the intake manifold.
 
- Remove the intake manifold  bolts.
 
- Remove the intake manifold.
 
- Remove the intake manifold gaskets (1) from
the intake manifold.
 
- Discard the old intake manifold gaskets.
 
- Clean the gasket surfaces of the EGR pipe and the exhaust manifold,  if
equipped.
 
Installation Procedure
- Install new intake manifold gaskets (1)
to the intake manifold.
 
- Install the intake manifold.
 
- Apply a 5 mm (0.20 in) band of threadlock GM P/N
 12345382 (Canadian P/N 10953489) or equivalent to the threads of the
intake manifold bolts.
 
Notice: Refer to Fastener Notice in the Preface section.
- Install the intake manifold bolts.
 
Tighten
- Tighten the intake manifold bolts a first pass in sequence to  5 N·m
(44 lb in).
 
- Tighten the intake manifold bolts a final pass in sequence to  10 N·m
(89 lb in).
 
- Install the EVAP purge  solenoid (3), isolator
(1), and bolt (2) to the intake manifold.
 
Tighten
Tighten the EVAP purge solenoid bolt to 10 N·m
(89 lb in).
- Install the EVAP purge  solenoid vent tube
to the solenoid (1) and vapor pipe.
 
- Install the accelerator control cable bracket
(2) to the intake manifold.
 
- Install the accelerator control cable bracket bolts (1).
 
Tighten
Tighten the accelerator control cable bracket bolts
to 10 N·m  (89 lb in).
Important: Lightly coat the MAP sensor seal with clean
engine oil before installing.
- Install the MAP sensor (1) to the intake manifold.
 
- Install the PCV hose (with  valve).
 
- If equipped, position  a new EGR pipe gasket
on the exhaust manifold.
 
- If equipped, install the EGR pipe (with valve).
 
- If equipped, install the following EGR pipe bolts until snug:
 
- If equipped, tighten the EGR pipe bolts.
 
Tighten
|     •  | Tighten the EGR valve pipe-to-intake manifold bolts to 10 N·m
 (89 lb in). | 
 
|     •  | Tighten the EGR valve pipe-to-cylinder head bolts to 50 N·m
 (37 lb ft). | 
 
|     •  | Tighten the EGR valve pipe-to-exhaust manifold bolts to 30 N·m
 (22 lb ft). | 
 
- Route the electrical harness into position over the engine.
 
- Connect the knock sensor  harness electrical
connector to the intake manifold.
 
- Connect the following electrical connectors.
 
- Install the fuel injectors. Refer to   
Fuel Injector Replacement 
  in Engine Controls - 4.8L, 5.3L, and  6.0L.
 
- Install the oil fill tube. Refer to 
Oil Level Indicator and Tube Replacement 
.
 
- Install the throttle body. Refer to   
Throttle Body Assembly Replacement 
  in Engine Controls - 4.8L, 5.3L,  and 6.0L.