Toyota Cressida/Corona/Crown/MarkII 1970-1982 Repair Guide

Catalytic Converter



Do NOT perform exhaust repairs with the engine or exhaust hot. Allow the system to cool completely before attempting any work. Exhaust systems are noted for sharp edges, flaking metal and rusted bolts. Gloves and eye protection are required. A healthy supply of penetrating oil and rags is highly recommended.

  1. Raise and support the vehicle on jackstands.
  3. Remove the heat shield.
  5. Some models have rubber O-ring supports; that may be in the way of removal, detach them, ensuring there is another support for the converter once removed.
  7. On some models you will need to remove the oxygen sensor. Unbolt the oxygen sensor and remove it. Protect the tip of the sensor from damage and do not place it on or near any petroleum based solvents. This includes putting it on a greasy rag.
  9. Remove the bolts at the front and rear of the converter.

Always support the pipe running to the manifold, either by the normal clamps/hangers or by using string, stiff wire, etc. If left loose, the pipe can develop enough leverage to crack the manifold.

  1. Remove the converter and gaskets.

To install:

  1. Check the rubber supports that hang the exhaust, they have a tendency to stretch and crack with age, replace if necessary.
  3. Using new gaskets, attach the converter to the exhaust pipes. Tighten the bolts to 29-32 ft. lbs. (39-43 Nm).

ALWAYS use a new gasket at each pipe joint whenever the joint is disassembled. Use new nuts and bolts to hold the joint properly. These two low-cost items will serve to prevent future leaks as the system ages.

  1. On models with the oxygen sensor in the catalyst, tighten the nuts to 14 ft. lbs. (20 Nm). Don't forget to connect the wire harness.