Contents: Removal ↡ Installation ↡
Removal
1. On 6-cylinder engines, depressurize the fuel system as described in paragraph 2.
2. Disconnect the negative battery terminal.
3. Remove the air cleaner as described in paragraph 3.
4. Where provided, loosen the bolts and remove the linkage bracket from the air flow sensor and move it to the side.
5. Disconnect the return spring of the lever mechanism on the throttle body and the connecting rod. Where appropriate, disconnect the lever mechanism of the constant speed actuator from the throttle lever.
6. Disconnect the vacuum hoses from the throttle body. Label them to avoid confusion during installation.
7. Disconnect the throttle switch plug from the connector.
8. Unscrew the nuts securing the housing to the intake manifold.
9. Loosen the large clamp on the rubber connecting sleeve between the housing and the air flow sensor (see fig. 9.9).
Fig. 9.9. Loosen the large clamp (shown by arrow) on a rubber connecting sleeve
10. On 6-cylinder engines, the entire fuel distributor assembly must be removed from the intake manifold - refer to item 14 for information. On 4-cylinder engines, perform the steps described in items 11-13 inclusive.
11. Remove the two nuts securing the air flow sensor to the rubber mounts at the end of the throttle linkage.
12. Unscrew the nut of the fuel drain line fitting on the back of the fuel pressure regulator and disconnect the fuel line. Be prepared for some gasoline to leak out.
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13. Carefully lift the air flow sensor upward so that the throttle body can be removed.
14. Loosen the mounting bolts and remove the housing from the intake manifold.
15. On 6-cylinder engines, remove the throttle body gasket. On 4-cylinder engines, use a sharp blade to cut and remove the middle portion of the intake manifold gasket that contacts the throttle body. Be careful not to scratch the mating surface.
Installation
16. Install the throttle body in reverse order. Note the following:
- a) If the throttle body is to be replaced, a new throttle switch must also be installed, as the two parts are matched as a pair.
- b) On 6-cylinder engines, install a new case gasket.
- c) On 4-cylinder engines, cut the middle section on the new gasket and place it in the throttle body mounting location (see fig. 9.16).
- d) Tighten the throttle valve mounting bolts to the required torque.
- d) Make sure that the vacuum hoses are installed correctly, according to the markings made during removal.
- e) When finished, check and, if necessary, adjust the idle speed as described in Chapter 1A.
Fig. 9.16. Cut off the middle part of the new intake manifold gasket and place it on top of the throttle body mounting area