How do you get the upstream sensor out?
It's in a bad spot. Seems impossible to remove. Any help would be appreciated.
2.5L v6
I just spent 3 hours and achieved nothing. Zilcho.

 

Which one? Front bank or rear? The front bank should be easy to get to with the right tool. There are two different types of O2 sensor sockets, both have a slot to accomodate the wire harness. One is low profile in design, should work better on the rear bank. The deep socket design might be better for the front bank.
Sometimes the end of the threads gets crudded up. That make it very difficult to get the sensor out. If you encounter a great deal of resistance, try running it back in, then out and in a few times to break off the crud rather than trying to drag it through the threads.

 

It's the front, or upstream, sensor. It is on the exhaust pipe right before the catalytic converter. The problem is there is no space to work.
I have the kit from Autozone for removing sensors, but making no progress.
I am tempted to take off the intake manifold and try to reach t from above.
That doesn't look promising either.

Very frustrated.

Thanks for your help.

 

Just finished this job on a 1999 last night. I think in 2000 they move the O2 sensor to the front exhaust pipes from just in front of the cat were it is on pre 2000 sebrings. This is a PITA!

In my experience the most important tool you need for this job is a source of heat, such as a propane torch (plumbers torch ?? you can get at any hardware store). I have never gotten a stuck O2 sensor off using brute force without screwing up the bung threads. If you are going to have to use a big breaker bar to get it loose STOP and break out the heat first otherwise you are most likely going to damage the threads in the bung.

Get your wrenches set up so that you can loosen the sensor.

I used a couple of 3/8 extensions (probably 18 inches total) with a flex on the end to the O2 crowfoot socket. I had to tape the socket to the flex to keep it on. I had to use another 2 foot piece of rod to help maneuver the socket onto the sensor, can’t get two hands up in there. Once you had that setup get the socket off of the sensor so you can apply heat.

Heat
I used a couple of 8 x 12 inch aluminum sheets I had as a heat shield. I bent them in an arch shape and slide them up over the cat so that they were above the O2 sensor and covered a wiring harness that is in that area.

WARNING: The torch is HOT it will burn rubber, wires, skin, etc. really fast. SAFETY FIRST! Have a fire extinguisher and water handy to put out fires and to cool anything you might accidently heat up such as your skin! Practice with no flame how you are going to light the torch and move it into position to apply the heat without burning anything else.

I then used a propane torch to heat the bung (place O2 sensor screws into) till it was red hot. You don’t need it to be glowing brightly red but just noticeably red without direct light on it. If you have a bright light on it you might not even see that it is beginning to get red.

Now get your socket set up in place without burning yourself. It should break loose without too much effort. Oh remember since you are working from the backside of the sensor you need to turn it CLOCKWISE to remove it. After I turned it a couple of times I let it cool. It tightens up a little but it shouldn’t be a problem from then.

Be careful when you reinstall the new sensor. It is hard to get it started in the hole squarely and you need to take care so that you don’t twist the wires too much and damage them. If you have a helper they can hold the connector on the top side of the engine so it doesn’t twist up.

Good Luck it took me three hours and I got to the heat pretty quickly.

RedBeard55

 

Oh also you can't get to it from the top either. Although I don't know how you could disconnect the wiring without removing the upper intake. I was also doing my plugs so I had removed the upper intake. But at least on the 99 I don't see how you could get to it.

 

thanks so much for your guidance. I am not comfortable with the torch under the car, so I will continue to see what else I can do.
I am thinking of cutting a hole in the floorboard so I can get an impact wrench down on it. Going to try another tool first I am looking for first. Ratcheting wrench with hinge. Would certainly grab it better.

Funny. I did remove the intake man and plugged in a new sensor. it's lying in the structure of the body until I can get the old one out. Now the engine light is OFF. funny, the sensor is not even inserted in the exhaust pipe, but it extinguished the engine light.

if that holds I am going to get it inspected to at least get past that.

 

Have you tried warming up the engine a little? That area of the engine warms up faster than any other. I would try that before using a torch under there. Be careful not to burn your hands.

 

Thanks to all for help.
I took your advice and ran the engine to get the exhaust pipes hot.
I also found a 15 inch thin wrench at Sears.
Broke it loose on the first try.
Recommend picking up the ratcheting wrench as well. Made it easy to work with.
Don't even bother with the sensor socket made for the product. No room to maneuver.
Woohoo!
New one is in.
One concern, the engine light is still on.
I'm guessing it takes a few miles to reset?

 

If the light doesn't go out after a few driving cycles, then check for codes and re-check your work. People here have reported poor luck with Bosch sensors.
I trust there was anti-seize on the threads of the new one?

 

Yes, there was anti seize goop on it.
How long is a "driving cycle"?
I noticed when I first attached the sensor (before I could get it in to the exhaust line) the light went off immediately, and back on in a couple hours.
I did actually use the car with the new sensor pugged in and just hanging by it's wire for a couple hours. think It's heating unit could have burned out?
It is a bosche.

I will check the code and erase it. we will see if it reappears.
thanks again.