Contour Enthusiasts Group Archives Forums Modifications Duratec Maintenance Rear O2 Sensor is [censored] impossible!!!!

Pain in the ass is a huge understatement...

A 7/8 wrench doesn't work from the top.

There's no chance whatsoever from the bottom.

A slotted sensor socket is too tall from the top.

What else is there!??

I just did this about two weeks ago.. follow the how-to to the tee, once you move the wiring harnest around some, I was able to slip the wrench by were the coil pack is and my hand between the harnest and the engine block on the left side (if you are facing the engine.) I found it easier to disconnect the sensor and slip the closed end of the 7/8 wrench over the 02 sensor. Once you break it loose a little, you can remove it with your hands. Hope this helps.

-Matt

It sure is a PITA! We just did ours and found this out first hand.
The 7/8th wrench isn't working at all?? That's what we used. It's kinda tight but we used short turns of the wrench, it took a while to get it off. We worked from the top and underneath.
It took longer than an hour that's for sure. Quite a few swear words were flying around too.

My hands and arms are small enough to do everything from above, but the 7/8 wont slide over the sensor enough to break it free. Stripping it is the only thing that seems feasible. The damn engine block is too much in the way merely by millimeters...

I've tried and I've tried... The 7/8 doesn't work.

Do I need a deep offset wrench or what?

Ah.. such a PITA. I felt like the project car at SZ. EVERYONE stood around me and I felt liek a fool that I couldn't get this damn o2 sensor out myself. Nevertheless, after trying all of the hard things first.. we ran across an 02 socket that was small enough to get the job done. Autozone had a kit with the taller one you speak of, and a small one.

God, don't remind me about doing that again.

i found it easy to just remove the coil pack and go at it from the top...

Yeah, but what he's saying is his o2 sensor socket was too long (hit the firewall yet couldnt slip over the edge of the sensor) We ran into that at SZ and it was impossible without the smaller o2 socket

Actually, what I meant was that the sensor couldn't be loosened using a ratchet, sensor socket, extensions, and swivel joints. I did finally figure out that a 1" open end wrench could be used on the sensor socket with it in place. It was much easier than trying to use a 7/8" box end on the sensor itself.

The sensor socket was too long after I installed the new Bosch unit, since it's taller than the OEM unit. So, in my case, tightening was solved using a deep offset 7/8" box end. The deep offset wrench probably could have been used originally to loosen the OEM one, but I didn't have that tool yet and tried the sensor socket + 1" wrench first. The latter combo definitely provided more range of motion than any 7/8" wrench would anyway.

For more clarification, read my how-to I wrote up earlier.