Note: A new cylinder head cover gasket will need to be installed during installation.
Removal
1. Disconnect the negative battery cable.
2. According to the engine type (see Chapter 4, Section 3) remove the air filter assembly (or the air supply pipe to the exhaust manifold or throttle air valve housing), as needed.
3. On engines with an exhaust gas recirculation (EGR) system, disconnect the EGR system connecting hose or pipe from the EGR valve and, if necessary for access, from the exhaust manifold by removing the steel washers on the flange connections. After this, unscrew the support bracket bolt (if it is installed) and remove the tube or hose.
4. On the latest models of turbocharged engines with intermediate cooling (the radiator is mounted on top of the engine), disconnect the air supply line from the radiator and turbocharger and remove it.
5. On engines with a split intake manifold, remove the bolt securing the throttle body housing to the exhaust manifold support bracket. Disconnect the throttle release lever from the throttle body and high pressure fuel pump. After unscrewing the nuts and bolts, separate the upper part of the manifold from the lower one. Remove the gasket between these parts.
6. Disconnect all other hoses and pipes, as necessary, if they obstruct access to the cylinder head cover.
7. After unscrewing nine bolts, remove the cylinder head cover (see Figure 5.7). Remove and discard the gasket.
Figure 5.7. Unscrew the nine bolts and remove the valve cover from the cylinder head.
Installation
Figure 5.8. Cylinder head valve cover bolt tightening sequence.
8. Install in the reverse order of removal, but pay attention to the following points:
- a) If a cork gasket was originally installed, remove any traces that remain on the mating surfaces of the cover and cylinder head.
- b) Install the cover with a new gasket, then insert and tighten the retaining bolts in the sequence shown to the specified tightening torque (see figure 7 8).
- c) On engines with a split intake manifold, install a new gasket and tighten the bolts to the specified torque (see chapter 4).
- d) Install all other removed parts and assemblies, referring to Chapter 4, if necessary.