Exhaust manifold — removal and installation (Opel Astra G)

Single shaft (SOHC) engines

1. Disconnect the connector from the oxygen sensor.

2. Disconnect the exhaust pipe from the manifold.

3. Remove the heat shield of the manifold, having first disconnected the hot air outlet pipe.

4. Remove the caps from the spark plugs and use a special key to remove the heat shields from the spark plugs.

5. Evenly and gradually unscrew the bolts (nuts) and remove the manifold.

6. When installing the manifold, replace the manifold mounting bolts (nuts) and all gaskets. Lubricate the spark plug heat shield threads with high-melting grease.

Twin-shaft engines 1.4 and 1.6 l

7. Remove the upper engine cover by unscrewing the screws and removing the oil filler plug.

8. Disconnect the oxygen sensor connector, remove the sensor wire from the brackets.

9. Disconnect the exhaust pipe from the manifold.

10. Loosen the bolts and remove the manifold.

11. When installing the manifold, replace the manifold mounting bolts (nuts) and all gaskets.

Engine 1.8 l

12. Remove the upper engine cover by unscrewing the screws and removing the oil filler plug.

13. Drain the liquid from the cooling system. Disconnect the hose from the thermostat.

14. Remove the heat shield from the manifold by unscrewing the 3 bolts (see photo). Loosen the bolt and move the oil level indicator pipe to the side.



15. Unscrew the nuts and remove the manifold (see photo).





16. When installing the manifold, replace the manifold mounting bolts (nuts) and all gaskets.

Engine 2.0 l

17. Remove both mounting eyes from the engine.

18. Loosen the front hose clamp on the cylinder head. Do not disconnect the hose.

19. Remove the heat shield from the manifold by unscrewing the 3 bolts.

20. Unscrew the bolts (nuts) and remove the manifold (see photo).

21. When installing the manifold, replace the manifold mounting bolts (nuts) and all gaskets.