O2 Sensor Replacement

[compguy101101]

Does anyone know a way to replace the firewall side downstream O2 sensor. It is quite difficult to get to and I cant get enough torque on it to loosen it.



And just FYI for anyone that is looking for info on placement of the O2 sensors. I got bad information and had to trial and error the whole thing.

Bank 1 is on the firewall side.
Bank 2 is the Radiator side.

Sensor 1 on both sides is the highest sensor on the engine. Sensor 2 is nearest the ground.

[compguy101101]

Since there was such an overwhelming response I ended up finding the solution myself and decided to share.

What I tried was spraying some PB Blaster (penetration oil) on the stuck O2 sensor while the engine was hot. Step back quick if you do this otherwise you'll breathe in some vapor when it steams off the heat shield because its scalding hot. Tried using my 7/8th's stubby wrench and it wouldn't budge. Found out that Auto Zone will rent out specialty tools and the O2 sensor socket just so happens to be a specialty tool. So went up to my local Auto Zone and for about $25 bucks rented the socket I needed. They give you the money back when you return the socket. They are about $10 dollars to buy. You'll need a universal joint and at least 20 inches of socket extensions and that is with removing the strut bar. You'll need 25 inches of you leave it in place. But there is a good angle on the O2 sensor and just a little turn and it was loose. Don't loosen it when the engine has just been running. I had some decent gloves on and it started melting the finger pads even though the car had been off for a good half hour. Put the replacement O2 sensor in place and clear the code when you return the socket.

[kendotelie]

thank you so much for this...i thought bank 2 sensors were near the firewall

[maxpower]

I'll throw a late reply on here. I found the specialty socket to be useless for removal. So much force is required to budge the thing that the socket just slips. Considering that you're more than likely just throwing away the old socket, just cut the wires off and put a regular socket on it.

Here's where it got sketchy for me, not even a breaker bar would budge it. So I put a piece of pipe on my breaker bar, it got it off and pretty much melted the threads in the mean time. So now the new sensor won't go in and I can't drive it with a hole in the manifold.

Thankfully the manifold threads are stronger than the 02 sensors threads so the 02 sensor took the bulk of the damage. I was able to clean up the manifolds threads with a thread chaser and put the new one in. You will need the specialty socket to put the new sensor in.

[JesterheadGTS]

Thank you for the info! Ive had an O2 Bank 2 Sensor 2 code for 2 months now, and couldnt figure out which sensor it actually was. Just curious if this is for the 3.8L v6?

[07Galant_GTS]

Thank you for the info! Ive had an O2 Bank 2 Sensor 2 code for 2 months now, and couldnt figure out which sensor it actually was. Just curious if this is for the 3.8L v6?

Yupp, I still have Bank 2 Sensor 1 code for the last couple months with my 2007 GTS, but need to get it inspected and will be tackling this problem this weekend...