Destruction of My Random Technologies Catalytic Converter

October 2003


I try to do my part in protecting our environment for future generations, so I run cats on all my cars.  Well, look what happened to the cat on my 1990 Nissan 240SX after less than 3 months and 3000 miles of use.  My 240SX has a SR20DET motor in it.  The cat has 3" inlet and outlet and the rest of the exhaust system is 3" throughout.  To tell you the truth, I have had absolutely no problems with the Random Technologies cats on my 91 Nissan 300ZXTT.  I have even participated in many autocrosses and track events with them on my Z.  Therefore, I really did not do any research when it came time to pick a cat for my 240SX.  Well I guess I should have, because after the fact, I discovered that others have had similar issues with the 240SX cats.  The research also yielded that many people were running Catco cats and had experienced no problems with them.  The guys at Enjuku Racing confirmed this by stating that they had been selling Catcos for over two years and had not heard of a single failure.

What started all of this was a very loud rattling noise emanating from under the car.  After getting the car on a rack, we shook things looking for the source of the noise.  We narrowed it down to the cat.  After removing it, here is what we found.

Here is a picture of the exposed side that clearly shows that the element has broken lose and is basically free to rattle around in the cat housing


Here is the view from the other end.  You cannot see it, but behind that mesh is another element that has also broken loose and is rattling around inside the housing.


Happy Motoring,



90 240SR

91 300ZXTT

01 Audi S4