Contents: Removal ↓ Installation ↓
Caution: Wait until the engine has cooled down completely before starting this procedure.
Removal
1. Disconnect the ground wire from the batteries (see paragraph 1 of chapter 5).
2. Raise the front of the vehicle and place reliable supports underneath it. Remove the lower engine guard (fig. 6.5).
Caution: If the vehicle is equipped with electronically controlled air suspension, turn off the ride height control switch.
3. Apply penetrating oil to the bolts and springs that secure the exhaust pipe to the exhaust manifold. After the bolts are saturated, remove them. Separate the exhaust pipe from the manifold, being careful not to damage the oxygen sensor (Fig. 9.3).
Fig. 9.3. Working under the vehicle, remove the bolts securing the exhaust manifold to the intake manifold (A) and lower the manifold. Be careful not to damage the oxygen sensor (C). (B) — bolts securing the exhaust manifold lower brace
4. Unscrew the bolts and remove the lower exhaust manifold clamps from the engine. Disconnect the electrical connectors of the oxygen sensors.
5. While working in the engine compartment, remove the upper heat shield from the manifold (Fig. 9.5).
Fig. 9.5. Working from the engine compartment, remove the upper heat shield mounting bolts...
6. Loosen the nuts/bolts, disconnect the manifold and remove the gasket (Fig. 9.6).
Fig. 9.6. ...and unscrew the exhaust manifold mounting nuts, then remove the manifold from the studs on the cylinder head and remove it from the engine compartment
Installation
7. Using a scraper, remove all traces of old gasket material and carbon deposits from the mating surfaces of the cylinder head and manifold. If the gasket shows signs of leakage, use a straightedge to check the manifold mating surface for flatness. If the mating surface is warped, the manifold should be replaced.
8. Install the new gasket, using the studs on the cylinder head as a guide and paying attention to the direction marks or arrows on the gasket (if any).
9. Install the manifold and tighten the nuts that secure it.
10. Working from the center outward, tighten the nuts/bolts evenly in three or four stages to the specified torque shown in Specifications at the beginning of this chapter.
11. Reinstall the remaining components in the reverse order of removal.
12. Start the engine and check for leaks in the exhaust system.