Exhaust gas analyzer Exhaust gas analyzer An exhaust gas analyser or exhaust CO analyser is an instrument for the measurement of carbon monoxide among other gases in the exhaust, caused by an incorrect combustion, the Lambda coefficient measurement is the most common. The principles used for CO sensors (and other types of gas) are infrared gas sensors (NDIR) and chemical gas sensors. "Carbon monoxide sensors are" used to assess the CO amount during an MOT test. In order to be used for such test it must be approved as suitable for use in the scheme. In UK a list of acceptable exhaust gas
Exhaust gas recirculation the engine was running. Difficult starting, rough idling, and reduced performance and fuel economy resulted. By 1973, an EGR valve controlled by manifold vacuum opened or closed to admit exhaust to the intake tract only under certain conditions. Control systems grew more sophisticated as automakers gained experience; Chrysler's "Coolant Controlled Exhaust Gas Recirculation" system of 1973 exemplified this evolution: a coolant temperature sensor blocked vacuum to the EGR valve until the engine reached normal operating temperature. This prevented driveability problems due to unnecessary exhaust induction; NOx forms under elevated temperature conditions generally not present with a cold engine. Moreover, the