2001 Rover 25 oxygen sensor

PETER LEWIS123

MEMBER
2001 ROVER 25
4 CYL
2WD
MANUAL
91,000 MILES

I was just wondering can anyone tell me the function of the oxygen sensor is. I think the mechanic I use is giving me false information on what the function of this part is?

Wednesday, August 19th, 2009 AT 6:21 AM

1 Reply

DAVE H

MECHANIC
13,383 POSTS

Heated Oxygen Sensor (HO2S)
The heated oxygen sensors are mounted in the exhaust manifold and pipe. HO2S sensor uses a built-in heating circuit. The heating circuit is used to bring the HO2S sensor up to operating temperature, enabling faster conversion to closed-loop operation.
HO2S monitors oxygen content of exhaust gases. When HO2S is at operating temperature, a signal between zero and 1.1 volts is produced. A signal less than.4 volts is produced when there is a high oxygen content in exhaust gases (lean air/fuel ratio). A signal of.6 volts or more is produced when there is a low oxygen content in exhaust gases (rich air/fuel ratio). Signal is transmitted to the PCM and is translated into a rich or lean mixture signal