Upper
REMOVAL
1. Disconnect battery ground cable. Refer to Starting and Charging.
2. Remove air cleaner outlet tube. Refer to Powertrain Management.
3. Remove accelerator cable shield from accelerator cable bracket.
4. Remove accelerator retracting spring and disconnect accelerator cable and speed control actuator cable from throttle body lever.
5. Remove two accelerator cable bracket retaining bolts from side of throttle body. Remove accelerator cable bracket and position out of way.
6. Remove vacuum hose from fuel pressure regulator.
7. Completely loosen EGR valve to exhaust manifold tube nut at EGR valve (EGR valve).
8. Disconnect EGR backpressure transducer hoses from the EGR valve to exhaust manifold tube.
9. Remove crankcase ventilation hose, aspirator vacuum supply hose and evaporative emission return tube from fittings underneath upper intake manifold.
10. Disconnect engine control sensor wiring connections to idle air control valve (IAC valve), throttle position sensor (TP sensor), EGR backpressure transducer and EGR vacuum regulator solenoid.
11. Drain engine cooling system.
12. Disconnect degas tube from radiator coolant recovery reservoir and lower intake manifold fitting.
13. Remove retaining nut and bolts for upper generator brace and remove brace.
14. Remove engine control sensor wiring bracket from throttle body retaining stud bolt and position engine control sensor wiring out of the way.
15. Remove intake manifold support from the throttle body and RH cylinder head.
16. Loosen and remove the upper intake manifold retaining bolts and stud bolts (note location for installation).
17. Lift and remove upper intake manifold from lower intake manifold.
18. Discard intake manifold upper gasket.
19. If required, remove degas tube from the upper intake manifold.
20. If required, remove EGR valve, EGR backpressure transducer and EGR vacuum regulator solenoid.
21. If required, remove the throttle body from the upper intake manifold. Refer to Powertrain Management.
22. If required, remove the idle air control valve. Refer to Powertrain Management.
INSTALLATION
CAUTION: Use care when cleaning gasket material because aluminum gouges easily which forms leak paths.
NOTE: Lightly oil all bolt and stud bolt threads prior to installation.
1. Clean and inspect sealing surfaces of intake manifold and throttle body.
2. Install guide pins (if available).
3. If removed, install idle air control valve to the upper intake manifold.
4. If removed, install the throttle body to the upper intake manifold.
5. If removed, install the EGR valve, EGR backpressure transducer and EGR vacuum regulator solenoid.
6. If removed, install degas tube to the upper intake manifold. Tighten retaining bolts to 8-12 Nm (71-106 inch lbs.).
7. Place intake manifold upper gasket on lower intake manifold.
8. Aligning bolt holes, install upper intake manifold on lower intake manifold. Install stud bolts and retaining bolts. Tighten to 20-30 Nm (15-22 ft. lbs.).
9. Install generator brace to upper intake manifold mounting stud and generator mounting bracket. Tighten nut and bolts to 12-20 Nm (9-14 ft. lbs.).
10. Install intake manifold support to the throttle body and RH cylinder head. Tighten retaining bolts as shown in the illustration.
11. Install the engine control sensor wiring bracket onto the throttle body retaining stud bolts.
12. Connect crankcase ventilation tube, aspirator vacuum supply hose and evaporative emission return tube to fittings underneath upper intake manifold.
13. Install EGR valve to exhaust manifold tube to EGR valve. Tighten to 35-65 Nm (26-47 ft. lbs.).
14. Connect vacuum hose to fuel pressure regulator.
15. Connect engine control sensor wiring connections to idle air control valve, throttle position sensor, EGR backpressure transducer and EGR vacuum regulator solenoid.
16. Install accelerator cable bracket to side of throttle body. Tighten retaining bolts to 17 Nm (13 ft. lbs.).
17. Connect accelerator cable and speed control actuator cable to throttle body lever. Install accelerator retracting spring.
18. Install accelerator cable shield. Tighten bolts to 1.4 Nm (13 inch lbs.).
19. Install air cleaner outlet tube. Refer to Powertrain Management.
20. Connect battery ground cable. Refer to Starting and Charging.
21. Fill engine cooling system.
22. Start engine and check for vacuum and exhaust leaks.
NOTE: This adjustment must be performed if the throttle body is removed for any reason and if throttle plate idle adjustment screw position is changed.
23. Check engine idle. Adjust as necessary. Refer to Powertrain Management.