Removal/refitting

The performance of the catalytic converter is greatly influenced by:

• temperature of exhaust gasses:

  The chemical reactions which take place in the catalytic converter are of the oxygen reducing type a process occurring normally in nature at temperatures around 1000 to 1200°C. The presence of noble metals allow these reactions to take place at lower temperatures (250 to 300°C). These temperatures are reached by the exhaust gasses with the engine running at normal speed.

• engine air-fuel ratio:

  Overall the pollutants present in the exhaust gasses are at a lower level when the air-fuel ratio of the mixture burned by the engine is approximately equal to the theroretical stoichiometric ratio (14.7:1). Under these conditions the catalytic converter is able to reduce the concentrations of the polluting substances contained in the exhaust gasses by 80%. It is for this reason that the Lambda probe is used.

REMOVAL/REFITTING

1. Place the vehicle on a lift.

• Raise the vehicle.
  1. Unscrew the bolts securing the forward and rear flanges to the catalytic converter and, after disconnecting the flexible support rings, remove the converter.
  2. Remove the gasket.
  3. Remove the seal ring.