Installing a Replacement Catalytic Converter

Like if this guide is helpful

Dismounting the old Cat

  1. Disconnect the earth cable of the battery.
  2. Lift the vehicle and ensure that it is locked safely in position.
  3. Loosen and dismantle the lambda sensor carefully from the converter if fitted.
  4. Loosen the fixings and bolts of the converter. If they are stuck, spray rust removing oil and /or heat the bolts with a gas torch. If you use a torch, ensure that it does not ignite the bottom surface of the vehicle.

Mounting the new Cat

  1. Thoroughly clean the fixing flanges/pipes to ensure a gas tight connection to the new converter. Under NO circumstances should you use any sealer or paste, as this could potentially damage the performance of the converter.
  2. Install new gaskets and fixing bolts. Mount the new Cat. Usually there is an arrow which indicates the correct exhaust gas direction.
  3. Mount the lambda sensor if applicable.
  4. Before tightening the bolts to the final tension, ensure that the converter has space to move without touching the vehicle body.
  5. Lower the vehicle to the floor, connect the earth cable of the battery and ensure the rigidity of the exhaust system.


Diagnose the root cause of the converter failure and FIX it before mounting the new converter - otherwise it will cause the new converter to fail as well.
Have something to share, create your own guide... Write a guide
Explore more guides