The law requires you to have a catalytic converter on
your vehicle. (Well, most vehicles, anyway.) But what does a
catalytic converter actually do? Why do you need one?
- How do I know when the
catalytic converter on my vehicle needs to be replaced?
The best way to determine if the
catalytic converter has failed is by testing the exhaust with
testing procedures like those used in state and local inspection
programs. However, the following symptoms may also indicate a need
for converter replacement:
- Broken or rusted out converter body or end tubes.
- Bits of substrate in other sections of the exhaust
system.
- No rattle in a pellitized converter (If the converter
doesn't rattle, the pellets may have melted together or fallen
out.
- A rattle in a monolithic converter (A rattle in this kind of
converter indicates the substrate has separated.)
- My Technician was talking about the OBDII on my
vehicle. What is that?
OBDII references the second generation of
On Board Diagnostic used initially in California and now in all 50
states. It is a computerized engine and emission monitoring system
designed to alert the driver that emission control service is
needed.
- What is the connection between
OBD and Vehicle emissions?
The vehicle computer will detect a system
problem before the driver notices a driveability problem. OBD can
also detect problems that might be noticed by visual inspection
because they can be electrical or even chemical in nature. By
detecting these emissions-related failures and alerting the driver
to the need for potential repair, EPA hopes that vehicles will be
properly repaired before emissions become a problem.
- How does OBD inform drivers of problems?<
When the OBD system determines that a
problem exists, a corresponding "Diagnostic Trouble Code" is
stored in the computer's memory. The computer also illuminates a
dashboard light indicating "Service engine Soon" or "Check Engine"
or displays an engine symbol. This light, usually yellow in color,
serves to inform the driver that a problem has been detected and
vehicle service is needed. When the vehicle is delivered to the
repair shop, a technician can retrieve the stored diagnostic
trouble codes from the computer memory of the vehicle. It is
important to note that an illuminated dashboard light, as
described here, is intended to inform the driver of the need for
service, NOT of the need to stop the vehicle. However, service
should be sought as soon as possible. Drivers may also wish to
consult a repair shop or their vehicle owner's manual for further
guidance.
- Why does the dashboard light
blink or flash?
Under certain conditions, the dashboard
light will blink or flash. This indicates a rather severe level of
engine misfire. When this occurs, the driver should reduce speed
and seek service as soon as possible. Sever engine misfire over
only a short period of time can seriously damage emission control
system components, especially the catalytic converter, which is
typically the most expensive to replace. Drivers should also
consult their vehicle owner's manual for manufacturer specific
instructions.
- How can the dashboard light be
turned off?
After fixing the problem, the service
technician will reset the fault codes, turning off the dashboard
light. The vehicle's OBD system can turn off the dashboard light
automatically if the conditions that caused a problem are no
longer present. For example, if the gas cap is not properly
tightened after refueling, the OBD system can detect the vapor
leak that exists. If the gas cap is tightened, the dashboard light
should be extinguished within a few drives.
- How does OBD help the
environment?
The intent of OBD systems is to assure
proper emission system operation of all vehicles over its lifetime
by monitoring emission related components and systems for
malfunction and/or deterioration. An important aspect of OBD is
its ability to notify the driver of a problem before the vehicle's
emissions have increased significantly. If the vehicle is taken to
a repair shop in a timely fashion, it can be repaired before any
significant emission increase occurs.
- How does OBD help consumers?
OBD systems are designed to alert drivers
when something in the emission control system begins to
deteriorate or fails. Early diagnosis followed by timely repair
can often prevent more costly repairs on both emission control
systems and other vehicle systems that may effect vehicle
performance such as fuel economy. For example: a poorly performing
spark plug can cause the engine to misfire, a condition sometimes
unnoticed by the driver. The engine misfire can, in turn, quickly
degrade the performance of the catalytic converter. With an OBD
detection of the engine misfire, the driver would be faced with a
relatively inexpensive spark plug repair. However, without an OBD
detection, the driver could be faced with an expensive catalytic
converter repair in addition to the spark plug repair. OBD systems
also provide far more information than ever before to help auto
technicians properly diagnose and repair vehicles during periodic
maintenance, or their first visit to the repair shop, saving time
and money for consumers.
943 Blue River Parkway
The purpose of the exhaust/emissions system is to deaden the sound made by the internal combustion engine, reduce the temperature of the exhaust, and control the emissions that come out of your vehicle. Vehicles create harmful gases during the combustion of fuel. The catalytic converter in the exhaust system turns these gases into mostly harmless ones that do much less damage to the environment.