Understanding the Exhaust Gas Readiness Monitor

A Comprehensive Guide to the Exhaust Gas Readiness Monitor in Modern Engines

The exhaust gas readiness monitor is responsible for monitoring the exhaust gases that are emitted by the engine and ensuring that they are within acceptable limits. The monitor works by measuring the levels of various gases in the exhaust stream and sending this information to the engine control unit (ECU). The ECU then uses this information to adjust the engine’s performance to ensure that the emissions are within the legal limits.

The exhaust gas monitor works by using a series of sensors that are placed throughout the exhaust system. The sensors d to measure the levels of

Carbon monoxide (CO)
Nitrogen oxides (NOx)
Particulate matter (PM).

The NOx sensor is the most important

The NOx sensor measures the levels of nitrogen oxides in the exhaust

NOx sensor

stream. Nitrogen oxides are a major contributor to air pollution and can cause a variety of health problems, including respiratory issues and heart disease. The NOx sensor is designed to detect these gases and send a signal to the ECU when the levels are too high. The ECU then adjusts the engine’s performance to reduce the emissions.

The Particulate Matter Sensor

Another important sensor in the exhaust gas monitor is the PM sensor. This sensor is responsible for measuring the levels of particulate matter in the exhaust stream. Particulate matter is a type of air pollution that is made up of tiny soot particles that can be harmful to human health. The PM sensor is designed to detect these particles and send a signal to the ECU when the levels are too high. The ECU then adjusts the engine’s performance to reduce the emissions.

particulate matter sensor

The catalytic converter is also part of the Exhaust Gas Readiness Monitor

The catalytic converter is responsible for converting harmful gases into less harmful ones. It works by using a series of chemical reactions to break down the harmful gases into less harmful ones. The catalytic converter is an essential component of the exhaust gas monitor and is required by law in most countries.

The Exhaust Gas Sensor Monitor is a “Two-Trip” Monitor. If a fault is found on the first trip, the computer temporarily saves the fault in its memory as a Pending Code. The computer does not
command the MIL on at this time. If the fault is sensed again on the second trip, the computer commands the MIL “On,” and saves the code in its long-term memory.

©, 2022 Rick Muscoplat