Note: The intake manifold consists of an upper section and a lower section. Removing the upper intake manifold is only required for some jobs (e.g. maintenance of fuel injectors/spark plugs), while some other jobs require the removal of both the top and bottom assembly (e.g. cylinder head maintenance). If it is necessary to remove the entire assembly, see section «Inlet manifold assy» in this section.
Removal procedure
1. Disconnect the cable from the negative battery terminal.
2. Remove the decorative engine cover. See «Decorative engine cover» in this section.
Attention! When disconnecting the throttle body wiring harness, the following precautions must be observed.
- To disconnect the connector (1) throttle body harness (2) do not use any mechanical tools such as a screwdriver.
- Taking away the lock (3) throttle cable connector, care must be taken not to disconnect it from the connector.
- Do not pull on the connector wires.
3. Take away the lock (3) throttle cable connector.
4. Pressing the connector lock in the direction of the arrow (4), disconnect the throttle body wiring connector.
5. Disconnect the hose (1) forced crankcase ventilation and vacuum hose (2) purge adsorber SUPS.
6. Remove bolts (3) fixing the pipe bracket between the expansion tank and the water outlet.
7. Remove bolt (4) fastening the bracket for the EVAP adsorber purge valve.
8. Disconnect the wiring harness connector from the intake manifold adjustment valve (IMTC).
9. Remove the engine wiring harness connector mounting bracket.
10. Move from the upper intake manifold all parts that are close to it.
Attention! After removing the upper intake manifold, plug each of the holes in the lower intake tracts with a lint-free cloth to prevent foreign material from entering the engine.
11. Remove four long (3) and two short (2) upper intake manifold bolt (1) to the cylinder heads and to the lower intake manifold.
Attention! Do not reuse the gaskets between the upper and lower intake manifolds.
12. Separate the upper intake manifold from the lower half, and then remove from the engine.
13. Remove and discard gaskets (4), located between the upper and lower intake manifolds.
14. Remove solenoid valve (5) IMTC throttle body assembly (6), if required.
Clear
Attention! Since the intake manifold is made of aluminum alloy, do not use wire brushes and steel scrapers to clean it, because. this may damage the sealing surfaces. It is preferable to use wooden or plastic scrapers.
1. Clean mating surfaces, removing all gasket residues.
2. Clean manifold with suitable solvent.
3. Dry the components of the gas distribution mechanisms with compressed air.
Inspection
1. Inspect the intake manifold, checking for the following faults:
- Damaged sealing or mating surfaces.
- Damaged lower intake manifold gasket.
- Damaged or excessively dirty threaded or through holes.
- Cracked or damaged intake manifold housing.
2. Lay the ruler (1) across the sealing surface (2) upper intake manifold.
3. With a probe (3) measure the gap between the manifold and the ruler.
4. If the gap between the top manifold sealing face and the bar is greater than the specified maximum warp, replace the manifold.
- Upper manifold max buckling: 0.05mm
5. Lay the ruler (1) across the sealing surface (2) lower intake manifold.
6. With a probe (3) measure the gap between the manifold and the ruler.
7. If the gap between the bottom manifold sealing face and the bar is greater than the specified maximum warp, replace the manifold.
- Lower manifold maximum warpage: 0.05mm
Installation procedure
1. Installation should be carried out in the reverse order of removal, taking into account the following.
- Only new gaskets need to be installed between the upper and lower manifolds.
Attention! Tighten the intake manifold bolts in a circle, starting at the center bolt and working out from the center.
2. Install the upper intake manifold.
Tighten
Tighten the bolts securing the upper intake manifold to the lower intake manifold and to the cylinder head to 23 Nm (17 lb-ft).
3. Connect the IMTC connector.
4. Connect throttle connector.
5. install bolt (4) fastening the bracket for the EVAP adsorber purge valve.
6. Install bolts (3) fixing the pipe bracket between the expansion tank and the water outlet.
7. Connect vacuum hose (2) ESU and positive crankcase breather hose (1) to the upper intake manifold.
8. Install the engine wiring harness connector mounting bracket.
