Technical Car Experts Answers everything you need: how to replace intake Manifold on 1997 toyota tacoma?

Intake Manifold

REMOVAL & INSTALLATION

5VZ-FE Engine

Fig. Use a ratchet to remove the upper intake manifold bolts

Fig. Once all the fasteners have been removed, lift off the upper intake manifold

Fig. View of the upper intake manifold and its bolt locations

Fig. Remove the upper intake manifold gasket from the lower intake runners

Fig. The upper intake manifold gasket may be made from several steel shims riveted together

Fig. Remove the middle-to-lower intake manifold bolts

Fig. Once all fasteners have been removed from the middle intake manifold, lift it off the lower intake manifold

Fig. Inspecting the intake manifold gasket for cracks or deterioration

Fig. Stuff shop towels into the intake runners to prevent dirt and debris from entering the engine

Fig. View of the middle intake runners

Fig. View of the lower intake manifold after it has been removed from the vehicle

The 5VZ-FE engine uses what could be called a three-piece intake manifold. The upper part (Toyota calls it an air intake chamber assembly) mounts the throttle body. The middle part is called an intake air connector assembly, jointing the air intake chamber with the lower manifold. The lower part is considered the actual intake manifold, bolts to the engine and mounts the fuel injectors. Toyota uses aluminum for many engine parts. Use care when working with light alloy parts as they are easily damaged.

CAUTION

Fuel injected engine systems remain under pressure after the engine has been turned OFF. Properly relieve the fuel pressure before disconnecting any fuel lines. Failure to do so may result in fire or personal injury.

Fig. Exploded view of the upper and lower intake manifolds1999 Tacoma with 5VZ-FE engine

Fig. Mounting bolt locations on the upper, middle and lower portions of the intake manifolds1999 Tacoma with 5VZ-FE engine

Relieve the fuel system pressure. For additional information, please refer to the following topic(s): "Fuel System," "Relieving Fuel System Pressure."

Disconnect the negative battery cable.

Drain the engine coolant.

Remove the air cleaner hose.

Disconnect the following cables:

On cruise control vehicles, the actuator cable with bracket

Accelerator cable

On automatics, the throttle cable

Tag for identification, then disconnect the brake booster hose, the EVAP hose, and if 4WD equipped with Automatic Disconnecting Differential (ADD), disconnect the ADD vacuum hose.

Disconnect the fuel return and fuel feed hoses.

Remove the upper intake manifold (air chamber) brace (Toyota calls it a stay). Remove the two bolts holding the throttle cable clamp, and then remove the two bolts holding the brace.

Remove the No. 2 timing belt cover. This is the cover that goes over the cam belt sprockets. It will be necessary to disconnect the four spark plug cable clamps that run across the top of the cover. Then remove the six retaining bolts and carefully separate the cover from the engine. Look for the wire from the Camshaft Position Sensor and detach the connector, if required.

At the upper intake manifold (air intake chamber), disconnect the following:

Throttle Position (TP) sensor connector

Idle Air Control (IAC) connector

Two PCV hoses

Two water bypass hoses

Remove the nuts and bolts holding the upper intake manifold (air intake chamber) assembly. Discard the gasket.

Remove the middle part of the intake manifold assembly (air connector) by unbolting the engine ground wire, disconnecting the fuel return hose, if not done so already, and the vacuum line to the fuel pressure regulator. Detach the Diagnostic Connector (DLC1) from the bracket. Remove the nuts and bolts and separate the middle part of the intake manifold. Discard the gasket.

Locate the engine wiring harness protector. Detach the six fuel injector connectors, the Engine Coolant Temperature (ECT) sensor connector(s) and unbolt the wiring harness protector assembly from the cylinder head.

Disconnect the fuel pressure regulator.

Remove the nuts and bolts from the lower part of the intake manifold and carefully work the manifold free of the cylinder heads. Discard the gasket.

To install:

Clean all parts well. Pay particular attention to the gasket sealing surfaces. Use care not to damage the light alloy parts.

Installation is the reverse of the removal process. Always use new gaskets. Carefully place the lower part of the intake manifold to the cylinder heads. Make sure all flat washers, nuts, and bolts are installed. Tighten to 160 inch lbs. (18 Nm), working from the center fasteners, outward.

Install the engine wiring harness protector and attach all removed connectors.

Using a new gasket, install the middle part of the intake manifold (air connector). Install the nuts and bolts and tighten to 160 inch lbs. (18 Nm), working from the center fasteners, outward.

Place the Diagnostic Connector (DLC1) back on its bracket. Connect the engine ground wire and all of the vacuum hoses detached at removal, using the identification tags made earlier.

Using a new gasket, install the upper part of the intake manifold (air chamber). Install the nuts and bolts and tighten to 160 inch lbs. (18 Nm), working from the center fasteners, outward.

Connect all remaining wires, hoses and cables, as required.

Install the timing belt cover and air cleaner hose.

Refill the engine with fresh coolant. Test run the engine and check for coolant and vacuum leaks.

1FZ-FE Engine

The 1FZ-FE engine uses what could be called a two-piece intake manifold. The upper part (Toyota calls it an air intake chamber assembly) mounts the throttle body. The lower part is considered the actual intake manifold, bolts to the cylinder head and mounts the fuel injectors. Toyota uses aluminum for many engine parts. Use care when working with light alloy parts as they are easily damaged.

Fig. Upper and lower intake manifolds and related componentsLand Cruiser with 1FZ-FE engine

CAUTION

Fuel injected engine systems remain under pressure after the engine has been turned OFF . Properly relieve the fuel pressure before disconnecting any fuel lines. Failure to do so may result in fire or personal injury.

Relieve the fuel pressure. For additional information, please refer to the following topic(s): "Fuel System," "Relieving Fuel System Pressure."

Drain the engine coolant.

Remove the battery and the battery tray.

Remove the air cleaner hose and cap.

Disconnect the following cables:

On cruise control vehicles, the actuator cable from the throttle body

Accelerator cable

Throttle cable (auto transmission)

Disconnect the engine ground straps from the engine hanger and from the upper half of the intake manifold.

Detach the connection on the intake manifold from the left fender apron.

Disconnect the brake booster and EVAP hoses.

Separate the fuel inlet and return lines from the fuel rail.

Disconnect the heater hoses and the radiator inlet and bypass hoses.

If necessary for clearance, remove the alternator and its bracket.

For more working room, remove the dipsticks for the engine oil and automatic transmission. Remove the mounting bolts and pull the dipstick tubes straight out. The O-rings should be replaced at assembly.

Remove the intake manifold brace (Toyota calls it a "stay").

If necessary for clearance, remove the two nuts and take off the water outlet pipe. The gasket must be replaced at assembly.

Locate and disconnect the EGR pipe from the cylinder head and intake manifold.

Remove the retaining nuts and bolts and remove upper and lower intake manifold as an assembly. Use care and make sure all vacuum connections are tagged for identification and disconnected, including the Thermal Vacuum Valve (TVV) hoses. Discard the gaskets.

To install:

Installation is the reverse of the removal process. If separated, install the air intake chamber (upper) and intake manifold (lower) assembly:
1. Inspect the new manifold-to-head gasket. There should be a notch in the gasket that indicates that end should be placed to the rear. Install the new gasket so that the rear mark is toward the rear of the cylinder head, near the EGR pipe opening in the head.
2. Tighten the intake manifold nuts and bolts evenly to 15 ft. lbs. (20 Nm), working from the center, outward.
3. Connect the vacuum hoses to the TVV.

Connect the EGR pipe to the head and the intake manifold.

Using a new gasket, install the water outlet pipe.

Install the manifold brace.

Using new O-rings, install the engine oil and automatic transmission dipstick tubes.

If removed, install the alternator and bracket.

Connect the fuel lines and the vacuum line to the brake booster. Connect the EVAP line and engine ground.

Connect the accelerator cable, automatic transmission throttle valve cable and the cruise control cable.

Install the air cleaner and pipe and the battery bracket. Install the battery.

Refill the engine with fresh coolant. Test run the engine and check for coolant and vacuum leaks.

2RZ-FE and 3RZ-FE Engines

The 2RZ-FE and 3RZ-FE engines use what could be called a "two-piece intake manifold." The upper part (Toyota calls it an air intake chamber assembly) mounts the throttle body. The lower part is considered the actual intake manifold and bolts to the cylinder head. Toyota uses aluminum for many engine parts. Use care when working with light alloy parts as they are easily damaged.

Fig. Upper and lower intake manifolds and related components2RZ-FE and 3RZ-FE engines

CAUTION

Fuel injected engine systems remain under pressure after the engine has been turned OFF . Properly relieve the fuel pressure before disconnecting any fuel lines. Failure to do so may result in fire or personal injury.

Relieve the fuel pressure. For additional information, please refer to the following topic(s): "Fuel System," "Relieving Fuel System Pressure."

Drain the coolant.

Disconnect the accelerator cable, the automatic transmission throttle valve cable (if equipped) and the cruise control cable (if equipped) from the throttle body.

Remove the air cleaner lid, detach the Mass Air Flow (MAF) meter electrical connector and the intake air connector pipe.

Disconnect the EGR pipe at the upper intake manifold.

Remove the intake manifold brace (Toyota calls it a "stay").

Tag for identification and remove the following:

EVAP hose from the throttle body

Brake booster vacuum hose

Water bypass hose from the water bypass pipe

Water bypass hose from the cylinder head rear cover

Locate and remove the nuts and bolts that hold the upper intake manifold to the lower intake manifold. Discard the gasket.

Locate and remove the nuts and bolts that hold the lower intake manifold to the cylinder head. Please note that if are clearance problems with the fuel rail and injectors and they need to be removed, use the following procedure:
1. Tag for identification the fuel injector connectors and detach the connectors.
2. Remove the fuel inlet and return lines.
3. Remove the two bolts that retain the fuel rail. Carefully lift the fuel rail upwards with the injectors. Use caution. The fuel injectors will tend to drop out of the fuel rail.

To install:

Clean all parts well. Check the sealing surfaces of the intake manifold parts. Using a precision straightedge and feeler gauge, check all of the sealing surfaces for warping. Maximum distortion allowed is 0.0078 inch (0.20mm). If the distortion is greater than this, the manifolds may not seal properly. The parts should be replaced.

Using a new gasket, install the lower half intake manifold to the cylinder head. Torque the nuts and bolts to 22 ft. lbs. (29 Nm).

If removed, install the fuel injectors and the fuel rail. Connect the fuel lines using new seals.

Using a new gasket, Install the upper half of the intake manifold. Torque the nuts and bolts to 15 ft. lbs. (20 Nm).

Connect all the hoses removed earlier, install the manifold brace and the EGR pipe.

Connect the accelerator cable, automatic transmission throttle valve cable and the cruise control cable.

Install the air cleaner and pipe.

Refill with coolant. Test run the engine and check for coolant and vacuum leaks.

2UZ-FE Engine

The 2UZ-FE engine uses a two-piece intake manifold. The upper part mounts the throttle body. The lower intake manifold bolts to the cylinder heads and hold the fuel rails and injectors. Toyota uses aluminum for many engine parts. Use care when working with light alloy parts as they are easily damaged. Note that on this engine, the starter motor is mounted to the lower intake manifold, facing to the rear, engaging the flywheel at the top.

Fig. Upper and lower intake manifolds and related components2UZ-FE engine

CAUTION

Fuel injected engine systems remain under pressure after the engine has been turned OFF . Properly relieve the fuel pressure before disconnecting any fuel lines. Failure to do so may result in fire or personal injury.

Relieve the fuel pressure. For additional information, please refer to the following topic(s): "Fuel System," "Relieving Fuel System Pressure."

Drain the coolant.

Disconnect the accelerator cable, the automatic transmission throttle valve cable (if equipped) and the cruise control cable (if equipped) from the throttle body.

Disconnect the fuel lines.

Detach the following connectors from the intake manifolds:

Throttle Position (TP) sensor

Accelerator pedal position sensor connector

Throttle control motor connector

EVAP control connector

Eight fuel injector connectors (tag first)

Engine Coolant Temperature (ECT) sensor and water temperature sender gauge connections

Eight ignition coil connectors (tag first)

Two heated oxygen sensor connectors

Tag for identification and detach the following hoses from the intake manifolds.

Vacuum hose from the fuel pressure regulator

PCV hose from the PCV valve on the left side head

Three EVAP hoses

Power steering vacuum hoses from the intake manifold

If not equipped with a hydraulic brake booster system, disconnect the brake booster vacuum tube

Disconnect the accelerator cable from the throttle body and remove the wire clamps.

Disconnect the water bypass hose from the front water bypass joint.

Disconnect the engine wiring harness retainers where it attaches to the right side fuel rail.

Remove the three bolts holding the engine wiring harness protector from the rear water bypass joint, on both cylinder heads.

Remove the ground cables from both cylinder heads.

Remove the Diagnostic Connector (DLC1) from the throttle body cover bracket and remove the bracket from the intake manifold.

Remove the two nuts and the accelerator cable bracket from the intake manifold.

Remove the nuts and bolts and carefully lift off the upper and lower intake manifolds and the fuel rails as an assembly.

If required, remove the nuts and bolts and separate the upper and lower intake manifolds.

To install:

Clean all parts well. Check the sealing surfaces of the intake manifold parts. Using a precision straightedge and feeler gauge, check all of the sealing surfaces for warping. Maximum distortion allowed is 0.0059 inch (0.15mm). If the distortion is greater than this, the manifolds may not seal properly. The parts should be replaced.

Inspect the new gaskets. Factory-type gaskets should have a white painted mark to indicate facing upward. Use care to align the port hole of the gasket and cylinder head. Using two new gaskets on the cylinder heads, carefully lower the intake manifold assembly into place on the cylinder heads. Torque the nuts and bolts to 160 inch ft. lbs. (18 Nm).

Install the accelerator cable bracket, the throttle body cover bracket and connect the Diagnostic Connector to its bracket.

Connect the wiring, hoses and cables, using the identification tags made at removal. Verify that the fuel line connections are secure and that the fuel injector connectors are installed on the proper injector.