[V6-12v] V6 O2 sensor replacement, tips & tricks

[Tom Christiansen]

Folks,

I haven't actually replaced my O2 sensors yet, but I did break the 
old ones loose so they're ready to be replaced.

I was hoping someone could provide some tricks as to how to reach 
those darn sensors. That didn't happen. So  I figured it out. Here 
are my tips & tricks for other's enjoyment.

There's much talk on-line about removing the sensors while the 
exhaust is hot. It's a common trick to heat up a rusted part to free 
up a bolt, sensor, etc. so that seemed like a good idea. Also, many 
people suggest that you use penetrating oil to make the job of 
loosening the sensors a bit easier. As someone pointed out, that 
might not be such a hot idea as if the oil gets on the sensor 
element, it'll likely be fried by the time the oil cooks onto the 
sensor. So here's what I came up with (follow at your own risk & expense):

Try first without penetrating oil. After a longer drive fetch your O2 
sensor socket (or 22 mm crowfoot), 1/2" drive breaker bar (mine is 
18" length), extensions. BEWARE OF HOT ENGINE. Attack the right 
(passenger side) sensor. That one is straight forward. I don't think 
I even had to use a U-joint on it. It just popped right out.

The left sensor is a much bigger pain in the butt. It's visible from 
the top but hides under all sorts of connectors, hoses, brake lines, 
etc. I found that the least difficult way to get at it was to go 
behind the brake lines (between them and that black stiffener bar - 
or whatever it is). Use a 22 mm crowfoot (one of the 10-point types 
much preferred) - a 7/8" will work in a pinch. That angle allows you 
to use the black stiffener thingy as a support for the breaker bar.

So now I have two loose O2 sensors. Now I just need parts... 
Obviously, I also get a trouble code now... The pesky amber light 
indicates a 2332 error (bad O2 sensor).

Above was performed on a 1994 90S (5-sp, FWD).

Tom