o2 Sensor Help

Those O2 sensors can be a real %#$&@ to get out! There are some things you can try:

WD40 really isn't a good penetrant. It's just an all-purpose lubricant. Get a can of PB Blaster from the auto store and soak the sensor, then bang it a few times around the rim with a hammer (to shock the seam and let the penetrant in), and then let it sit overnight. Don't start the engine. The next day the sensor should crack loose if you put some muscle on it. If it still doesn't move, try heating the pipe around the sensor with a torch. This will expand it a little and maybe loosen the fit of the sensor threads. Also make sure that you have a long enough socket extention on your wrench so you can put some force on it. If you don't have a 18" 3/8ths socket extention and a flex-joint, this job is a good excuse to buy them!

If you buy a flex joint, just make sure you spend the money and get a name brand one. I actually fragged a cheap Chinese flex joint that I bought at a swap meet once. I wasn't using a cheater bar or anything- I was just bearing down on it and it snapped! I cut my hand pretty badly on the chassis when it let go, too. Another lesson to wear mechanic's gloves when you do something like that!

The front passenger side O2 sensor is the most difficult to remove due to clearance issues.I replaced all 4 of mine 2 years ago.With the pass side,even with an O2 socket,I still ended up rounding the edges off and yes tearing my knuckles up.What I ended up doing was breaking the end of the sensor off so I could get a regular full sized socket over it.I PD'd it multiple times prior.Once i broke the end off,I then had enough clearance and broke it loose.Do that,just use a pair of pliers and grab up as close to the base of the nut as possible.Or you can just whack it a couple times to break it.(You wont be needing it anyway).Once you get it out,apply some anti-seize compound to the threads of the new sensor.