Removal Procedure
Important: You do not have to remove the upper intake
manifold in order to remove the lower intake manifold.
- Remove the engine cover. Refer to
Engine Cover Replacement
in Interior Trim.
- Remove the air cleaner outlet duct from the throttle body. Refer to
Air Cleaner Outlet Resonator Replacement
in Engine
Controls-4.3 L.
- Remove the throttle body assembly. Refer to
Throttle Body Assembly Replacement
in
Engine Controls - 4.3L.
- Disconnect the accelerator control cable from the throttle shaft and
the accelerator control cable bracket. Refer to
Accelerator Control Cable Replacement
in Engine Controls-4.3 L.
- Disconnect the cruise control cable, if equipped from the throttle shaft
and the accelerator control cable bracket. Refer to
Cruise Control Cable Replacement
in Cruise Control.
- Remove the PCV valve hose assembly from the intake manifold and the valve rocker
arm cover.
- Remove the nut holding the engine wiring harness bracket to the intake
manifold stud.
- Remove the engine wiring harness bracket from the stud.
- Disconnect the following electrical connectors:
• | The A/C compressor clutch, if equipped (1) |
• | The A/C high pressure cutoff switch, if equipped (5) |
• | The throttle position (TP) sensor (2) |
• | The idle air control (IAC) motor (3) |
• | The fuel meter body assembly connector (4) |
- Disconnect the following electrical connectors:
• | The manifold absolute pressure (MAP) sensor (4) |
• | The EVAP canister purge solenoid valve (1) |
- Remove the engine wiring harness bracket
from the stud at the EVAP canister purge solenoid valve.
- Move and secure the engine wiring harness out of the way.
- Remove the EVAP canister purge valve to
Evaporative Emission Canister Purge Solenoid Valve Replacement
in Engine Controls-4.3 L.
- Disconnect the vacuum hose from the intake
manifold.
- Remove the bolt holding the transmission
fluid filler tube to the accelerator control cable bracket.
- Remove the accelerator control cable bracket
from the throttle body and the intake manifold.
- Remove the fuel lines from the fuel meter body assembly. Refer to
Fuel Hose/Pipes Replacement - Engine Compartment
in Engine
Controls-4.3 L.
- Remove the studs for the upper intake manifold.
- Remove the upper intake manifold.
- Remove the upper intake manifold gasket
from the groove.
- Discard the gasket.
- Remove the seal from the fuel meter body
assembly.
- Discard the seal.
Important: Do not immerse the assembled upper intake
manifold in cleaning solvent.
- Clean all sealing surfaces and the inside of the upper intake manifold with
a shop towel and cleaning solvent.
- Inspect the upper intake manifold for the following:
• | Cracks or other damage to the exterior |
• | Cracking or damage to the gasket grooves |
• | Loose or damaged bolt hole thread inserts |
- If replacing the upper intake manifold,
turn and remove the PCV valve cover from the upper intake manifold.
- Remove and discard the seal.
- Remove the throttle body if replacing the upper intake manifold. Refer
to
Throttle Body Assembly Replacement
in Engine Controls-4.3 L.
- Remove the MAP sensor if replacing the upper intake manifold. Refer to
Manifold Absolute Pressure Sensor Replacement
in Engine Controls-4.3 L.
Installation Procedure
- Install the throttle body, if removed.
Refer to
Throttle Body Assembly Replacement
in Engine Controls-4.3 L.
- Install the MAP sensor, if removed. Refer to
Manifold Absolute Pressure Sensor Replacement
in Engine Controls-4.3 L.
- Install the PCV valve cover, if removed, using the following procedure:
3.1. | Install a NEW seal (O-ring) on the PCV valve cover. |
3.2. | Lubricate the seal with clean engine oil. |
3.3. | Install the PCV valve cover in the upper intake manifold. |
3.4. | Turn and lock the PCV valve cover in position. |
- Install a NEW seal on the fuel meter body
assembly.
- Lubricate the seal with clean engine oil.
- Install a NEW upper intake manifold to
lower intake manifold gasket in the groove of the upper intake manifold.
- Install the upper intake manifold onto
the lower intake manifold.
- If reusing the fasteners, apply threadlock GM P/N 12345382
or equivalent to the threads of the upper intake manifold attaching bolts.
Notice: Use the correct fastener in the correct location. Replacement fasteners
must be the correct part number for that application. Fasteners requiring
replacement or fasteners requiring the use of thread locking compound or sealant
are identified in the service procedure. Do not use paints, lubricants, or
corrosion inhibitors on fasteners or fastener joint surfaces unless specified.
These coatings affect fastener torque and joint clamping force and may damage
the fastener. Use the correct tightening sequence and specifications when
installing fasteners in order to avoid damage to parts and systems.
- Install the upper intake manifold attaching studs.
Tighten
- Tighten the upper intake manifold attaching studs on the first pass to
5 N·m (44 lb in).
- Tighten the upper intake manifold attaching studs on the final pass to
9 N·m (80 lb in).
- Install the fuel lines to the fuel meter body assembly. Refer to
Fuel Hose/Pipes Replacement - Engine Compartment
in Engine
Controls-4.3 L.
- Install the EVAP canister purge valve. Refer to
Evaporative Emission Canister Purge Solenoid Valve Replacement
in Engine
Controls-4.3 L.
- Install the accelerator control cable bracket,
studs, and nuts to the intake manifold and the throttle body.
Tighten
Tighten the accelerator control cable bracket nuts
and studs to 12 N·m (106 lb in).
- Connect the vacuum hose to the intake manifold.
- Install the transmission fluid fill tube
and bolt to the accelerator control cable bracket.
Tighten
Tighten the transmission fluid fill tube bolt 6 N·m
(53 lb in).
- Position the engine wiring harness.
- Connect the following electrical connectors:
• | The A/C compressor clutch, if equipped (1) |
• | The A/C high pressure cutoff switch, if equipped (5) |
• | The throttle position (TP) sensor (2) |
• | The idle air control (IAC) motor (3) |
• | The fuel meter body assembly connector (4) |
- Connect the following electrical connectors:
• | The manifold absolute pressure (MAP) sensor (4) |
• | The EVAP canister purge solenoid valve (1) |
- Install the engine wiring harness bracket and nut to the intake manifold
stud.
Tighten
Tighten the engine wiring harness bracket nut to
12 N·m (106 lb in).
- Install the engine wiring harness bracket
and the nut onto the stud at the EVAP canister purge solenoid valve.
Tighten
Tighten the engine wiring harness bracket nut to
8 N·m (71 lb in).
- Connect the PCV valve hose assembly to the intake manifold and the valve rocker
arm cover.
- Install the cruise control cable, if equipped to the throttle shaft and
the accelerator control cable bracket. Refer to
Cruise Control Cable Replacement
in Cruise Control.
- Install the accelerator control cable to the throttle shaft and the accelerator
control cable bracket. Refer to
Accelerator Control Cable Replacement
in Engine Controls-4.3 L.
- Install the throttle body assembly. Refer to
Throttle Body Assembly Replacement
in
Engine Controls - 4.3L.
- Install the air cleaner outlet duct to the throttle body assembly. Refer
to
Air Cleaner Outlet Resonator Replacement
in Engine Controls-4.3 L.
- Install the engine cover. Refer to
Engine Cover Replacement
in Interior Trim.