Lexmex

Yes, it can be annoying given the area that it's in. I've seen the electrical connector and A/F sensor removed on a Camry at a Toyota dealer and it was a PITA for them, too.

Here's Bank 2, Sensor 1

Lexmex

And Bank 1, Sensor 1

CRAIGGREEN

thanks Bear and Lex. This will save me lots of money Pep Boys wanted over $800 to replace them.

code58

Please tell me you don't go to Pep Boys for your mechanical work. Kinda like going to Dunkin Donuts for your gourmet cup of coffee. Sorry, just not my idea of mechanics.

Lexmex

Manny, Moe and Jack seem like a great group of guys.

I won't go for service there (I don't need to), but in some smaller communities it can be an option for people. Some of my relatives in rural Illinois fall into this category there may not be other options particularly if they own a vehicle where the dealer is a long drive.

I do like shopping at Pep Boys for other things like fluids and they'd be number #1 in my book there.

trips1

I started with Bank2 Sensor 1 (the one behind the radiator and easily accessible). I sprayed PB blaster and left if for about 2 hours.
Whatever i do i am not able to get it out. I tried Sensor Socket, Open end wrench and also an elbow wrench which did allow the whole wire to pass through it.

I guess the sensor is very strongly sealed.
I am scared to use the hammer strokes on the wrench fearing that it may break the joint. Any more recommendations other than i take it to a mechanic

Is it advisable to use strong hammer blows on the wrench?

code58

Do you have access to an acetylene torch? In all the years I spent in automotive work, I never ONCE saw heat to fail in loosening the most seized nut or fitting. It is a lot better to use an acetylene torch because you can control right where the most heat is directed as opposed to a propane torch and also it needs to be heated quickly so that the outside (female) threads will expand before the inner (male) threads are able to expand with them. Concentrate the heat around the outside of the female threads so that they expand and release the hold on the sensor threads. Be ready to break it loose quickly (with BOX WRENCH) before it cools much or it will regain it's hold. I have NEVER had it to fail in all the years I worked in automotive. Even situations where NOTHING else in the way of "rust busters" would break it, the heat always worked. You need to get it a dull red at least! If you don't have the equipment to do it, maybe you can find a muffler shop that will do it that way for you. Good Luck!

P.S. Where are you in CA.? If you were in the OC area I would do it for you free of charge.

trips1

Really appreciate your response code58. I am in San Diego. I will get in touch with you if i find that i am not able to do it myself.

Aprazur

Try starting the engine and let it run for 10/20 min. Shut the motor off and put on some good gloves. Be careful (HOT). Put the box wrench on and try to loosen it.

Sometimes the heat of just running the engine for a few min will expand the joint enough to loosen it. If that don't work try the torch and put a cold wet rag on it after its hot. The cold will brake the rust loose on the hot joint.

If that don't work

Jerry

code58

NO COLD WET RAG! I've done this for almost 40 years and I can tell you for a fact, even with heating the outside of where the threads are, You have to move fast to get it unscrewed. As soon as it starts to cool from that red condition (which is quick!) it starts to seize again. There are times when the nut was big enough that I would have to heat again to get it all the way off. A cold wet rag will only put you right back where you started. The problem is RUST in the threads that is causing the seizing. You don't get it to "break loose" and then just spin it off. Often you even have to use a thread chaser to clean the rust from the threads in order for the new part to go on easily.

trips1

Thanks for all the comments. This is what i am planning to do. Would really appreciate in case i need any modifications to this.
(1)- Run the car for about 2 minutes.
(2)- Carefully put lot of PB blaster at the joint. Since it is going to be hot i will have to put PB Blaster from a distance. I hope there is nothing nearby that can get damaged from the PB Blaster fluid??
(3)- After about 2 hours try Sensor Socket. If that does not work use closed wrench at the sensor joint and hammer it lightly.
(4) If this does not work then leave the closed wrench on the sensor joint and run the car for about 5 minutes so that it heats up.
(5) Carefully try to hammer the closed wrench while the manifold is hot.

I am hoping this would work. I am just trying the front sensor which was quoted as much easier than the B1S1 that is underneath. I am now not too optimistic if i would be able to open it especially with so limited space underneath the car with floor jack and jack stands.

dkpnkc

I had the exact problem last week. I ended up taking it to the dealership to have the old sensor removed - I was worried I'd do something wrong and end up needing a new manifold. Took them a while to get it out. I had the part so I still saved some cash.

Makes you wonder about all those used manifolds on ebay that just happen to come with the sensor attached.

salimshah

I have not had the need to replace the sensor, but here are general guidelines.

The penetrating fluids work better if give them more time.

I would suggest. [imho step 1 is wrong or out of sequence and a bit dangerous]

With the manifold COLD spray the fluid. Put a rag and soak it on the sensor. Leave it there for overnight.

If you have the socket (split to run the wire), you can try putting on a clamp on top to prevent any spread. If it does not come out easy, then it is time to add heat. With open flame, make sure the rag soaked with penetrating fluid is off. [standard safety with open flame needs to be exercised]


DIYers typically would reach for a propane torch. MAP is an alternative fuel, which produces a bit more heat.

For stuck bolts, I try to unthread a bit and then thread back half way. This keeps the cut threads ready to accept the replacement. Also that is the time the penetrating fluid works back in ... so blast away as you do the partial rethreads.

Salim

Nad1370

This is how I took mine off.
I actually used Brake Fluid for a penetrant.
Works evrey time.

code58

Nad- what caused you to 1st use brake fluid for a penetrant? Somehow I feel you're pulling our leg on this one because I don't see any sign of fluid of any kind on the sensor. If true, it's the 1st time in my life I've ever heard of that.