BMW 18407556504 Exchange. Exhaust Manifold With Catalyst

To remove the exhaust manifolds on a 3.0L engine: Raise the front of the vehicle and remove the engine splash shield. Remove the nuts securing the manifold outlets to the exhaust system. Disconnect the electrical connectors for the oxygen sensors. Remove the cover over the ignition coils and the coolant expansion tank. Remove the rear and front exhaust manifolds, taking care not to damage the oxygen sensors. Discard the gaskets.

The catalytic converter is a reliable device that does not require maintenance itself. However, there are certain factors to consider for it to function properly throughout its service life.