Exhaust manifold — removal and installation (Opel Vectra A)

Note: When installing, use new gaskets between the manifold and cylinder head, and between the manifold and exhaust outlet pipe. Exhaust manifolds on models with two overhead camshafts (DOHC) are tubular in shape.

Removal

1. Disconnect the negative cable from the battery.

2. Disconnect the high tension wires from the spark plugs, if necessary, mark them to avoid confusion during installation.

3. Loosen the clamp screw and disconnect the air filter warm air tube from the housing on the manifold, if equipped. Unscrew the mounting screws, remove the air heating chamber from the manifold.

4. Working underneath the manifold, unscrew and remove the four bolts securing the exhaust outlet pipe to the manifold,

5. If equipped, disconnect the oxygen sensor wiring.

6. Separate the exhaust outlet pipe from the manifold, secure it with wire or twine. Do not let the front section of the exhaust system hang under its own weight. Remove the gasket.

7. Unscrew the fastening nuts, remove the manifold from the cylinder head (see illustration). Remove the gasket.

Material copied from this website [Opelbook.ru]



8. It is possible that some manifold struts may unscrew from the cylinder head when unscrewing the manifold mounting nuts. In this case, the struts must be screwed back into the cylinder head.

Installation

9. Install the manifold using a new gasket, tighten the fastening nuts to the specified tightening torque Specifications.

10. Connect the exhaust outlet pipe to the manifold using a new gasket, tighten the mounting bolts to the specified tightening torque Specifications.

11. Then carry out the installation in reverse order.