Catalytic Converter Care
A catalytic converter is a device which chemically converts
harmful exhaust gases, produced by the internal combustion
engine, into harmless
carbon dioxide and water vapor. The converter was developed
to meet stringent emission reduction levels as set forth
by the Federal ERA and California Air Resources Board. Since
the 1975 model year, vehicle manufacturers have used catalytic
converters and other emission control devices, to meet those
emission reduction levels.
Substrate is the material inside the shell of the converter.
There are two types of original equipment substrates: Pelletized,
which consists of thousands of BB-sized ceramic pellets and
Monolithic, which is a ceramic "honeycomb" style.
The replacement converters listed in this catalog have monolithic
Catalyst is a thin coating of precious metals (rhodium, platinum
and paladium) applied to the surface of the substrate material.
Its function is to assist in the chemical reactions that
are required to lower the emission levels.
In August, 1986, the U.S. Environmental Protection Agency
issued new guidelines for the construction, efficiency and
installation of aftermarket converters. The converters listed
in this catalog have been designed, tested, manufactured and
proven to meet the ERA policy and emission reduction requirements.
Replacement converters built before December 18, 1986 do not
comply with the latest EPA policy. The sale and/or installation
of those converters may be prosecuted as a tampering violation
of the Clean Air Act. Converters built after that date are
in compliance. Those converters are permanently labeled with
a date code by the manufacturer. The four digit code refers
to the month and year of manufacture (example: "0488" is "April,
When a Converter does not function, no exhaust gas conversion
takes place. Usually the vehicle will run fine, but it will
not pass emission test standards. This may be caused solely
by a worn or damaged converter. But, it is difficult to diagnose
because it involves other emission system components, as well.
The most common cause of this problem is lead contamination
within the converter. Use of leaded fuel is usually the source
of the contamination.
A Converter will get red hot when raw fuel is introduced directly
into it. This is not the problem of the converter itself, but
the result of a problem with the fuel system or ignition that
allows unburned fuel to pass through the engine to the converter.
Possible causes are improper ignition timing, fouled spark
plugs, and air pump failure.
If a converter is operated too long at a high temperature,
its substrate may "melt down" and turn into a solid
mass inside the converter. The vehicle may seem sluggish, as
if there were a loss of power. Again, an engine and/or fuel
system malfunction is allowing a rich fuel mixture to reach
the converter. If the problem is not diagnosed and corrected,
future converter failures may occur.
The air pump or check Valve could be malfunctioning. The universal
hoses listed in this catalog are made of a high temperature
(up to 550° F) Silicone rubber. Their purpose is to transport
air (up to 125° F) to the converter. Under proper operating
conditions they will not burn or melt. However, if hot exhaust
gases back-up from the converter into the hose, damage could
Many times on first start-up in the morning, the exhaust may
smell like "rotten eggs". This is due to rich fuel
condition with a cold engine. However, as the engine warms
up, this smell should go away. If it does not, converter damage
could possibly follow with extended driving.