Please excuse the question but I'm an older guy geting back into the car scene after a 15 year layoff. What is an oxygen sensor and what is it's purpose? My 93 Eg needs one and like to know how hard is it to install one or if I can go to a shop and have one installed and what type of shop would do this type of work? Time constraints ( work ) Thanks P.S does this have anything to do with the air to fuel ratio? My tach ( air /fuel ) is reading lean. thanks for any advice

 

an o2 sensor reads the content of o2 in exhaust and compares with atmospheric o2. the combined o2 generates a voltage to send to the ecu that triggers a/f ratio based on a table in the rom.

 

oh also the more o2 in the exhaust the leaner it is i think...lol

 

o2 sensors are easy to replace...get yours from oxygensensors.com

don't trust the air/fuel gauge, it is most likely wrong.

 

O2 sensor is located in the exhaust pipe, one before the cat, this one is key and adjusts fuel trim.. The other o2 is at the cat, it just reads air and has nothing to do with ecu..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PK SPEED &raquo;</TD></TR><TR><TD CLASS="quote">O2 sensor is located in the exhaust pipe, one before the cat, this one is key and adjusts fuel trim.. The other o2 is at the cat, it just reads air and has nothing to do with ecu..</TD></TR></TABLE>

that only applies if you have a OBD2 car aka 96+ where he has a OBD1 car which is the 92-95 yrs. For the OBD1 there's only one O2 sensor which sits in front of the cat and has 4 wires coming out of it.