Ok here I am again. hopefully a quick question and a quick east anwser. I have a 98 camary, replaced 02 sensor, but now I'm not sure if I have 02 sensors or A/F sensors, I guess they look alike. How do I tell the difference? thanks

 

What engine?

Look on the underside of the hood. Cars built to California standards should have a sticker stating "CALIF" or something to this effect. Cars built to FEDERAL standards used 02 sensors.

It was up to the individual states to decide which emissions standards cars first sold in the state must meet.

 

thanks for the info great help thanks again

 

Would not an A/F sensor have an extra wire or two over an O2 sensor? I think an A/F sensor is just a broad range 02 sensor??

Not a bad explanation:
http://www.aa1car.com/library/o2sensor.htm

 

This dpends on if the sensor has a heater or not. Later 02 sensors have a heater, the A/F sensor appears to have always had them.

The A/F sensor appears to be also called a wide band sensor. Thus yes it has a wider output range.

 

FAIL