The catalyst efficiency monitor verifies that the catalytic converter is operating at a high enough efficiency rating to keep exhaust emissions within predetermined values. The PCM compares the signals from the upstream and downstream oxygen sensors to determine the state of the converter. These “tests” are called the readiness monitors.
If you are replacing a catalytic converter for a customer, it is not the same as replacing a muffler or pipe. Since the catalytic converter is an emissions device that is federally and locally mandated, documentation is just as key as proper installation.
If the vehicle has any O2 sensor-related DTCs stored, pending or active, perform the repair procedure.
As part of OBDII, Mode$02 for the logging or freeze frame data was created. This diagnostic protocol saves data PIDs and information when a code is set. In 1995, freeze frame gave technicians a powerful diagnostic tool that was previously only available on expensive factory tools.
On some Mazda vehicles, a sulfur smell or rotten egg odor may be noticed coming from the exhaust system. The odor is usually noticed after a cold start, fast idle, extended periods of idling and full-throttle acceleration. The sulfur smell is not an indication of an engine concern and will not cause reduced driveability or durability of the engine or any of its emission components.
Today’s modern vehicles are equipped with a sophisticated emissions control device. These fail when the engine is not tuned up, as this leads to overworking the converter, overheating and possible clogging.
Andrew Markel explains how a scan tool can be used to detect a leak in the exhaust manifold. Sponsored by Auto Value and Bumper to Bumper.
The Diesel Particulate Filter (DPF) is a ceramic filter that has thousands of tiny channels or honeycomb-shaped openings that trap the soot onto the channel walls and prevent the particulate matter (down to 1 micron) from exiting out the tailpipe. The honeycombed inner structure is covered with a layer of a chemical catalyst that contains small amounts of precious metals, usually platinum or palladium.
The catalyst efficiency monitor verifies the catalytic converter is operating at a high enough efficiency rating to keep exhaust emissions within the predetermined values. The PCM compares the signals from the upstream and downstream oxygen sensors to determine the state of the converter. These “tests” are called the readiness monitors.
Andrew Markel explains the difference between closed and open loop operations, and which is more efficient. Sponsored by Bosch Automotive Service Solutions.
Andrew Markel goes over the composition of two types of oxygen sensors with a brief history into each. Sponsored by Bosch Automotive Service Solutions.
Andrew Markel explains how a mass air flow code and an oxygen sensor code on a Nissan Maxima can be solved with one simple check. Sponsored by Nissan.