On the 240s the 02 sensor is located in the front header pipe - on some 740s, I ve seen it in the pipe. I just bought a bosal front pipe that did not have a sensor hole.

If the cat I bought (arriving UPS) has a sensor hole (plugged)- can I use that hole for the 02 sensor instead of the header pipe? It seems to me it should not matter, but you never know. I know have a 740 with the sensor in the cat I think!

Plus, I just fought the "bushing from hell" last night and it won. A front control arm bushing with big bolt gauled into the sleeve - ahhhhgggg. This is why my independent garage does not like to do bushings on older cars - me too. I cut off the end of the bolt and still can't get it to come out. Have most of the rubber material drilled out and the sleeve just spins while laughing at me!! Going back for round two today - might try to just cut the whole bushing out!! Fire and torches are the last resort!!!!

Bob Weber
14 Hughes Court
Hamilton, Ohio 45013
513-863-6994
49 Volvos since 1979 and have gone bushing mad!

240's can have the O2 sensor either place. My '89 has it in the head pipe, my '90 has it in the cat.

-Ron

The weld-in bung for the O2 sensor is a cheap item, any muffler shop can add this for you... (If you do, have them put it such that you can remove the 02 sensor from above... much easier...)

The only disadvantages to moving it down to the cat are making the wires reach, and if you have an older unheated 02 sensor, waiting longer for it to heat up...

-Paul Demeo
1990 780T (02 sensor straight up just behind the turbo...)

It's an 89 and has the 3 wire sensor - didn't think it would be any big deal to use the cat senor hole.

I won the bushing battle after a hour of cutting it off with an air wheel cutter!

Bob Weber