Hey Survivor, ( i survived twice, hence the email name)

Any how, the post from Southern Fried Volvo is 100% accurate..I had the identical experience with my 91 240. The 3 wire universal is $39 at auto zone with a 90 warranty.

btw, i did not want to run 3 new wires from under the hood down to the new O2 sensor. While at Auto Zone, I had them look up the part number stamped on the plastic connector which came with the new O2 sensor. Turns out it is a Ford/Mercury connector that came on certain year taurus, cougar, etc...So, I went to the junk yard and pulled a couple of those connectors (no charge). After ensuring my new universal O2 sensor mated up with the ford connector (and it was the perfect fit) I then proceeded to cut off the old O2 sensor and solder the junkyard ford connector to the three wires. This provided me with a convenient socket under the car. Makes it a whole lot easier to pull the O2 sensor without having to twist and untwist the 3 wires when unscrewing the sensor!

The sensor works fine and never had another problem since..got about an extra 1/2 to 1 mpg too.

also, i soldered the 3 wires, double shrink-wrapped each connection, put some plastic flex wire conduit around the area and taped it closed. Sorta like micro surgery on a patient that can't sue ya.

good luck


mm49