Intake manifold (Multec multipoint injection) — removal and installation (Opel Astra F)

Removal

Disconnect the negative battery terminal.

Release the clamp, then disconnect the throttle cable end ball joint from the throttle cable arm. Remove the throttle cable rubber bushing from the bracket on the intake manifold and set the cable aside.

Loosen the screw and disconnect the air line from the throttle body.

Remove the nut and disconnect the brake booster vacuum hose from the intake manifold (fig. 4.118).



Disconnect the camshaft cover breather hoses from the throttle body.

Disconnect the vacuum hoses from the throttle body, marking their location for later installation.

Disconnect the coolant hoses from the throttle body (two hoses) and from the intake manifold (one hose), marking their location for ease of installation. Coolant leakage may occur, so clamp the ends of the hoses to prevent coolant leakage. If necessary, disconnect the coolant hose from the rear of the manifold.

Disconnect the electrical connectors from the throttle position sensor and the idle speed control motor located in the throttle body, as well as from the intake manifold temperature sensor.



Remove the two clamp bolts and disconnect the two ground wires from the right side of the cylinder head (fig. 4.119).



Disconnect the ground wire from the engine lifting eyebolt (located on the left side of the intake manifold).

Disconnect the wire from the coolant temperature gauge sensor located in the intake manifold.

Disconnect the plug connectors from the fuel injectors.

Disconnect the halves of the plug connector located on the bracket secured to the upper left stud of the intake manifold.

Disconnect the hoses from the fuel distributor (are located underneath it), noting their location for subsequent installation. The most convenient access is from under the car - if you wish, lift the front of the car and secure it with a stand under the drive axle. Slowly loosen the screws, reducing the pressure in the system. Fuel leakage is possible, so take fire safety measures. Clamp the ends of the hoses to prevent dirt from entering and fuel leakage (fig. 4.123, 4.124).











Remove the bolt and nut at the top of the generator.



Check and ensure that all relevant hoses, tubes and wires are disconnected.

After removing the nuts, remove the intake manifold and, if necessary, the ancillary components as described earlier.

Installation

Procedure for carrying out work: as indicated above in the subsection "Installing the intake manifold".