Why are broken or melted converters NOT covered under warranty?

 Quite simply converters are not the cause of the problem, but rather the result of a problem.  Why was the OE converter replaced in the first place?  If it was replaced because it was melted or broken what would lead you to believe that the same problem would not happen to a replacement converter?  Unfortunately most technicians do not look further into the problem, they just assume it is a "defective" converter and the reason it melted and broke up into pieces was because it was "defective".  Is it simply amazing how many techs buy into this way of thinking. 

There are NO moving parts inside a converter.  If a converter is installed with a brick ( substrate ) that is not broken what would cause this substrate to become broken?  The answer is thermal failure.  Thermal failure happens when the operating temperature of the converter exceeds 1200 deg F.  The general reason is fuel contamination due to some type of engine operating system malfunction.  When the engine runs in a rich air-fuel mixture, the excess fuel is forced into the converter via the exhaust system.  This un-burned fuel burns un-checked inside the catalytic converter and raises the internal temperature of the converter excessively. 

The first stage in the destruction of the catalytiic converter is the "burning off" of the precious metals.  They begin to move to the rear of the converter and the efficiency of the converter begins to drop at an exponential rate, thereby triggering the CHECK ENGINE light with a PO420 code ( catalyst in-efficiency).  At this point most technicians will simply replace the catalytic converter and claim to have solved the problem, rarely is it simply this easy. 

If the problem is more extreme, the next stage in the process is for the converter matting to be burned away.  This is the material that surrounds the "brick" inside the converter shell.  Once this matting is burned away the bricks begin to move around and rattling noises are most likely heard by the customer.  This normally occurs when internal temperatures reach between 1700 and 2100 deg F.  In about half of the cases when this occurs, the brick can actually rotate inside the converter shell and block the outlet of the converter, thus substantially restricting exhaust flow. 

The most dramatic, stage of the destruction process is when temperatures exceed 2100 deg F.  At this point the ceramic begins to break apart or melt or a combination of the 2.  It is a constant battle to educate technicians and customers on why their converter needs to be replaced, possible for the second time.  Most are open minded and willing to learn, some believe that there is nothing new for them to learn.  With todays high technology cars and trucks so many systems are related to each other and can affect one another, it is very important to think outside the box when diagnosing difficult problems.  If you have specific questions about your car or light truck, feel free to email us ! 

Located in Toronto, Canada we are expanding at a phenomenal rate!! Initially started as a vision and a two man operation, we now have 3 locations supplying hundreds of repair shops and dealerships across the province, and now across the country, including the United States. The majority of our business comes from the distribution of original replacement exhaust systems and catalytic converters, to the professional installer and muffler shops