Removal & Installation
- Before servicing the vehicle, refer to the Precautions section.
- Drain the cooling system.
- Relieve the fuel system pressure.
Remove or disconnect the following:
Negative battery cable
Install the lower intake manifold with a new gasket.
- Step 1: 35 inch lbs. (4 Nm)
- Step 2: 78 inch lbs. (9 Nm)
- Step 3: 70-84 inch lbs. (8-10 Nm)
Install or connect the following:
ECT sensor connector
- Fill the cooling system.
- Start the engine and check for leaks.
The intake manifold is a two-piece design. It consists of an upper half, also called the plenum, and a lower half, which is bolted to the engine. The throttle body, control cables, fast idle solenoid, idle air control solenoid and emission connections are mounted to the upper intake manifold. The fuel injectors are mounted in the lower intake manifold.3.3L Engines
Lower Intake Manifold
- Relieve the fuel system pressure. Please refer to Fuel System, Electronic Fuel Injection, Relieving Fuel System Pressure for the procedure.
- Remove the upper intake manifold (plenum) using the previous procedure.
- Disconnect the six fuel injector electrical connectors.
- Disconnect the engine coolant temperature (ECT) sensor electrical connector.
- Remove the two ground wire bolts.
- Disconnect the heated oxygen sensor electrical connector and unclip the harness from its bracket.
- Disconnect the PCV breather hose. Remove the wiring harness straps and position the hose and wiring harness aside.
- Disconnect the coolant temperature sending unit electrical connector.
Remove the bolt from the spark plug wire bracket and remove the bracket.
CAUTIONObserve all applicable safety precautions when working around fuel. Whenever servicing the fuel system, always work in a well ventilated area. Do not allow fuel spray or vapors to come in contact with a spark or open flame. Keep a dry chemical fire extinguisher near the work area. Always keep fuel in a container specifically designed for fuel storage; also, always properly seal fuel containers to avoid the possibility of fire or explosion.
- Remove the two bolts from the high pressure fuel line and disconnect it.
- Remove the clamp from the fuel return hose disconnect it.
- Remove the fuel injection fuel rail bolts, then position the fuel rail and the insulators out of the way.
- Remove the upper radiator hose from the intake manifold water outlet. Remove the upper radiator hose bracket bolt.
- Remove the upper timing belt cover bolt.
- Remove the bypass hose from the intake manifold water outlet.
- Disconnect the heater hose from the intake manifold pipe.
- Remove the lower intake manifold bolts and nuts in two steps. Refer to the illustration for the proper sequence.
- Remove the lower intake manifold washers. Lift the lower intake manifold from the engine. Discard the gaskets.
- The installation is the reverse of removal, but please note the following important steps.
- Clean the lower intake manifold and cylinder head gasket surfaces. A gasket scraper and solvent may be used, however, be careful not to nick or gouge either surface.
- Lay new lower intake manifold gaskets on the cylinder heads and position the lower intake manifold on the engine. Install the lower intake manifold washers, bolts, and nuts.
Tighten the lower intake manifold bolts and nuts as follows. Refer to the illustration for the proper sequence.
- Tighten the nuts and bolts, in sequence, to 35 inch lbs. (4 Nm).
- Tighten the nuts and bolts, in sequence, to 80 inch lbs. (9 Nm).
- Retighten the nuts and bolts to 80 inch lbs. (9 Nm), still following the tightening sequence.
After installation, fill the cooling system. Run the engine and check for fuel, coolant, and vacuum leaks.
Disconnect the negative battery cable.
CAUTIONNever open, service or drain the radiator or cooling system when hot; serious burns can occur from the steam and hot coolant. Also, when draining engine coolant, keep in mind that cats and dogs are attracted to ethylene glycol antifreeze and could drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantities. Always drain coolant into a sealable container. Coolant should be reused unless it is contaminated or is several years old.
- Drain the radiator and recycle the engine coolant.
Remove the air cleaner-to-intake manifold hose using the following procedure:
- Disconnect the vacuum hose, breather tube, and bypass air inlet hose from the air cleaner-to-intake manifold hose.
- Loosen the air cleaner-to-intake manifold hose clamps.
- Remove the air cleaner-to-intake manifold hose, with the upper and lower resonators still attached.
- Disconnect the manifold absolute pressure (MAP) sensor and MAP solenoid electrical connectors.
- Disconnect the two electrical connectors from the throttle body. Slide the harness from the bracket.
- Disconnect the idle speed control (ISC) electrical connector.
- Remove the coolant hose from the throttle body.
- Disconnect the evaporative emission (EVAP) vacuum hose from the throttle body.
- Remove the fuel pressu