Contents: Removal ↡ Installation ↡
Removal
1. Disconnect the negative battery terminal.
2. Contact paragraph 2 and depressurize the power supply system.
3. Contact paragraph 7 and disconnect the throttle cable from the throttle guide lever. On automatic transmission models, disconnect the pressure control cable from the linkage. On cruise control models, disconnect the throttle control linkage at the throttle actuator assembly.
4. Loosen the bolts securing the wiring harness bracket to the intake manifold after releasing the wires from it.
5. Remove the air cleaner.
6. Contact paragraph 10 and follow these steps:
- a) Remove the cold start valve from the intake manifold.
- b) Remove the air flow/fuel distribution sensor assembly.
- c) Remove the throttle body.
7. On 6-cylinder models with cruise control, remove the bolts and throttle actuator assembly and support bracket from the manifold.
Article obtained from this portal: MERCEDESMAN
8. Where provided, on 4-cylinder engines, disconnect the hoses from the idle air distributor; carefully label each hose to avoid confusion during assembly.
9. Loosen the union nut and disconnect the brake booster vacuum hose from the intake manifold. Release the hose from the bracket.
10. Where provided, on 4-cylinder engines, unbolt and remove the engine lift bracket from the manifold.
11. Disconnect the remaining plugs and vacuum hoses from the intake manifold, labeling each one to avoid confusion during installation.
12. Loosen the bolts and remove the support struts from the bottom of the manifold (see fig. 11.12). Check that nothing else is preventing the manifold from being removed.
Fig. 11.12. Intake and exhaust manifold parts - 4-cylinder engine
1 Exhaust manifold
2, 3, 7 Gasket
4 Support stand
5 Lid
6 Upper half of the intake manifold
8 Lower half of the intake manifold
13. Loosen and remove the mounting nuts and bolts. Then lift the intake manifold off the cylinder head. Remove the gasket.
14. Where provided, if desired, after unscrewing the mounting bolts, the upper and lower parts of the manifold can be separated. Note that when assembling, a new gasket must be installed between the two parts (on 4-cylinder engines, the gasket is also installed on the throttle body).
15. Carefully clean the mating surfaces of the cylinder head and manifold to avoid scratching them. Remove all traces of the old gasket. If a leak is suspected, check both surfaces for warpage using a metal ruler and feeler gauge (see Chapter 2).
Installation
16. Installation is carried out in reverse order, taking into account the following points:
- a) Before installing a new gasket on the cylinder head studs, make sure that both mating surfaces are completely clean.
- b) Contact paragraph 7 and adjust the throttle cable.
- c) On models with automatic transmission, refer to Chapter 7B and adjust the operation of the pressure control cable.
- d) Start the engine and check for leaks around the manifold.
- d) Check and, if necessary, adjust the idle speed as described in Chapter 1A.