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Why did my converter fail  ?

This is the first question that everyone should be asking, unfortunately 99.99% of the technicians, counter-people, and salespeople just say the following, "the converter was just defective."  This is the biggest misconception in the emissions business today, and it is simply due to the lack of knowledge on how converters function by the people making the statement.  Our converters are designed not only to meet, but to EXCEED government standards.  When the internal substrate is coated it goes through a weight check 5 times to ensure the proper amount of precious metals were applied, 15 quality control checks, and a back-pressure test.  As a result comments like, "the converter felt like it was plugged" or "it must have been defective from the factory" do not apply to our converter cores, if it was the case they simply would not pass the tests from the factory.

Generally, if a replacement converter fails it is the result of one of the following

1) the converter has not reached operating temperature.  Also, there is a special procedure to condition the converter before a smog test, this is normally found in most automotive operators manuals today

2)oil or coolant contamination or excess fuel

3)ignition problem, i.e. misfire.

Educating yourself is the key to understanding todays' emission control systems.  Regardless if you purchase a converter from us or not, ASK your technician WHY your converter need replacing and if they give you the line "because it is defective"  chances are they have no clue what caused the problem and you can be assured that the same thing WILL happen again to your replacement converter.

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 or third 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.  At the same time, you can use converters on modified vehicles without problems.  We have been using our line of converters for a number of year in cars ranging from turbocharged Honda engines to twin-turbo Mercedes AMG models with thousands of trouble free miles.  If you have specific questions about your car or light truck, feel free to email us !

We work closely with trained technicians on a daily basis for information and problem vehicles that they encounter on a daily basis.  Below is a list of some of the more common ones;

1) Nissan Altima 2.5L 02-06.  These cars are notorious for issues with the manifold converter assemblies.  There are a number of problems that lead to the destruction of converters,  aftermarket or OEM units.  They can be destroyed in as little as one day.  The following reasons will result in the destruction and/or break-up of the internal ceramic substrate; excess burning of engine oil, faulty primary O2 sensor, faulty ignition module, and or long service intervals.

2) Ford F-series 5.4L 04-08.  These trucks changed to a new design spark plug that if left in the cylinder head for more than even 35,000 miles tend to accumulate carbon deposits around the 'barrel' of the unit causing it to seize in the cylinder head.  Many techs are aware of this and will not attempt to change plugs on this truck for fear of breaking the spark plug in the cylinder head; once the plug is broken it requires the entire removeal of the cylinder head at major expense.  When this plug becomes old, mis-fires occur, and the end result is a damaged, broken, and/or melted converter

3) Audi A4 / VW Passat 1.8T.  These cars had a problem with faulty ignition packs.  This results in mis-fire and complete destruction of the ceramic substrate.  VW did recall some models in the US and replaced the ignition modules and solved the problem, however, there are still many models that have not been repaired properly and continue to have problems with damaged converters.

4) Mazda Millenia S 2.3L.  These cars are notorious for destroying rear manifold converters, this is the converter located between the engine and firewall.  The main cause are faulty ignition packs and faulty or lazy primary O2 sensors.  We have seen converters detroyed in as little as 20 miles.  If you own or are repairing one of these vehicles, make sure these problems are resolved OR you are pretty much garanteed that the replacement unit will fail again, including OE units.

4) Mazda Protege.  Models made from 1999 to 2003, with all engine sizes, go through the manifold mounted converters like there is no tomorrow, again the primary culprit is either a faulty ignition module and/or faulty or lazy primary O2 sensors.  This is a well known problem, and any one with one of these models should make sure they have and updated or non-faulty ignition module before attempting to replace a damaged converter.

4)Mazda MX5 Miata.  Models made from 1999-2002 have a well know problem with faulty ignition modules.  Cracks in the casing of the ignition modules allow moisture to seep in and cause mis-fires, damaging the converter in no-time.  The dealers are aware of this problem and most have had their modules replaced or updated.  If you are replacing a converter on this vehicle, make sure you have a properly funcitoning unit or the replacement converter will also be damaged.

This is just a small example of problem vehicles, everyone should do their own homework, which is simple as searching the intenet for 5 minutes, to determine the common problems with their cars or trucks before replacing a catalytic converter.  The original converter should never have to be replaced for melted or broken issues, if this has happened to your car then there IS A PROBLEM somewhere.  There are indeed some substandard units on the market, but even the very best or most expensive converter, including OE converters cannot withstand the above types of problems and survive !