[alphaae]

Trying to replace the oxygen sensors on my 2010 Rav 4. I failed an emissions test for my plates and I can't get new plates until I fix the problem.

I'm needing some help with this as I see several different answers but not sure which one is correct.

According to some forums on here, there are 4 different oxygen sensors for the vehicle. Others I have only seen 2 sensors. Which is the correct answer to this?

The error code I got was P0136, O2 Sensor Circuit Bank 1 Sensor 2.

The second question is should I replace all the sensors now or just replace the troubled ones? I'm sitting at about 94,000 miles right now.

 

[DL175]

For that one it is confusing as the real culprit is actually B1/S1 (Air Fuel Sensor) which is the downstream sensor. No don't replace all the sensor as the others may never fail.
Buy the Denso O2 sensor to ensure reliability.

 

[alphaae]

For that one, it is confusing as the real culprit is actually B1/S1 (Air Fuel Sensor) which is the downstream sensor. No don't replace all the sensors as the others may never fail.
Buy the Denso O2 sensor to ensure reliability.

I bought two sensors from Amazon because I wasn't sure who the real culprit was.

DENSO 234-9022 Air Fuel Ratio Sensor

Denso 234-4622 Oxygen Sensor

Which one is the right sensor? Just the Oxygen or Air Fuel Sensor?

 

[DL175]

I bought two sensors from Amazon because I wasn't sure who the real culprit was.

DENSO 234-9022 Air Fuel Ratio Sensor

Denso 234-4622 Oxygen Sensor

Which one is the right sensor? Just the Oxygen or Air Fuel Sensor?

Well if your car is the 2.5 then you will have only 2 sensors. The V6 has 4 sensors.

 

[DL175]

Here is one member who had a P0136 (B1/S2) he replaced with Denso 234-4622. After that he got another code. It got uglier after this. Here is the thread.

 

[@2011rav4]

You do have the 2.5l. 4 cyl?

Bank 1 Sensor 2. Denso 234-4622 is the cheapest so start with that one
If it doesn't clear the code then do B1 S1

1. Let us know how you make out

 

[st.ryder64]

I had a failed O2 sensor on my rear cylinder manifold early on. I replaced it...it was almost impossible to reach, but I got it. I still had a code. Took it to a dealer and he spent several days tshooting. Turned out, I replaced the right sensor, but I didn't get the connector completely pushed in. It was impossible to get two hands on the connector ends, and those weatherproof connectors are REALLY hard to cinch completely closed. With one hand, it's almost possible.

 

[alphaae]

Here is one member who had a P0136 (B1/S2) he replaced with Denso 234-4622. After that he got another code. It got uglier after this. Here is the thread.

oh man. I hope that's not the case.

 

[@2011rav4]

B1 S2 is an easy one to change on the 2.5l. Just make sure you spay it good with PB Blaster or something similar and let it sit for a while

If you don't have a 02 sensor wrench you use a 22mm box wrench with a piece of pipe for leverage to get it off.

 

[alphaae]

I had a failed O2 sensor on my rear cylinder manifold early on. I replaced it...it was almost impossible to reach, but I got it. I still had a code. Took it to a dealer and he spent several days tshooting. Turned out, I replaced the right sensor, but I didn't get the connector completely pushed in. It was impossible to get two hands on the connector ends, and those weatherproof connectors are REALLY hard to cinch completely closed. With one hand, it's almost possible.

IM assuming this is the one thats

B1 S2 is an easy one to change on the 2.5l. Just make sure you spay it good with PB Blaster or something similar and let it sit for a while

If you don't have a 02 sensor wrench you use a 22mm box wrench with a piece of pipe for leverage to get it off.

I bought a sensor socket from Amazon when I got the sensors. Hoping that helps to make the job easier.

 

[@2011rav4]

Just MAKE SURE you spray it good with BP BLASTER and let it soak in the threads of the sensors before you take them out
I would let it work overnight if you have the time
.good luck . Let us know how you make out.

 

[alphaae]

Got to the sensor and started to work on it. Unfortunately it’s stuck very tight. I’ve poured about half a can of penetrating lubricants to try and get it out but still nothing. Going to let it set for the night and see if I can get it in the AM.

Sensor -1
Mechanic - 0

 

[@2011rav4]

Spray it a couple of times. It's going to be tight
You may need a pipe or something to put on the handle of you wrench to give you some leverage to break it free. Or a breaker bar if you have one. Make sure you put the anti seize on the new one before you put it in.

 

[Techsus]

PB Blaster excellent suggestion. Let soak overnight, yes, then reapply in the a.m. Also, AutoZone will lend you a set of flare (line) wrenches if you don't have your own set.

 

[alphaae]

Well, I finally got it out but it took more work than I thought. Because of the location of the sensor, I couldn't get enough leverage on it to break the rust and remove the sensor. So I decided to go next level and remove the exhaust pipe section with the sensor.

First I popped out the sensor clip mounted to the engine to discount the wires. (It's easier to access this by removing the passenger tire and taking off the panel that covers your serpentine belt.)

Then I removed the two spring bolts under the engine towards the front of the car

Next, I removed the two bolts on the back of the pipe towards the mid of the car. (This is a picture of the two bolts to remove this section of the exhaust pipe.)

Tip: because these back bolts are exposed to the elements it can be really tough to break them loose. I ran my car for 15 minutes for each bolt to heat up the pipe and make it easier to turn. I also used Liquid wrench to help with the process.

Once I removed those 4 bolts I was able to remove the exhaust pipe section with the oxygen sensor on it.

Once I had the pipe out I was able to get more leverage using an adjustable plumbers wrench and a hammer get the sensor. I was able to tap the wrench with the hammer to knock it loose.

Threads where good so I was able to put an anti-seize compound and put the new sensor in.

Then I just reversed the process and connected everything back up.

After I started the car up and all the error lights turned off and the car runs like normal.

Now off to the emissions testers tomorrow to get my plates renewed.

Thanks for all the help and suggestions on the forum. I hope this guide can help anyone else who needs to get this job done and is having a hard time getting it done.

2010 TOYOTA RAV4 2.4 cyl

 

[ravenuer]

Great post, thanks!

 

[@2011rav4]

Well, I finally got it out but it took more work than I thought. Because of the location of the sensor, I couldn't get enough leverage on it to break the rust and remove the sensor. So I decided to go next level and remove the exhaust pipe section with the sensor.

First I popped out the sensor clip mounted to the engine to discount the wires. (It's easier to access this by removing the passenger tire and taking off the panel that covers your serpentine belt.)

View attachment 146875
View attachment 146876
View attachment 146879

Then I removed the two spring bolts under the engine towards the front of the car
View attachment 146877

Next, I removed the two bolts on the back of the pipe towards the mid of the car. (This is a picture of the two bolts to remove this section of the exhaust pipe.)

Tip: because these back bolts are exposed to the elements it can be really tough to break them loose. I ran my car for 15 minutes for each bolt to heat up the pipe and make it easier to turn. I also used Liquid wrench to help with the process.
View attachment 146878

Once I removed those 4 bolts I was able to remove the exhaust pipe section with the oxygen sensor on it.
View attachment 146880

Once I had the pipe out I was able to get more leverage using an adjustable plumbers wrench and a hammer get the sensor. I was able to tap the wrench with the hammer to knock it loose.

View attachment 146881
View attachment 146882

Threads where good so I was able to put an anti-seize compound and put the new sensor in.
View attachment 146883

Then I just reversed the process and connected everything back up.
View attachment 146884

After I started the car up and all the error lights turned off and the car runs like normal.

Now off to the emissions testers tomorrow to get my plates renewed.

Thanks for all the help and suggestions on the forum. I hope this guide can help anyone else who needs to get this job done and is having a hard time getting it done.

2010 TOYOTA RAV4 2.4 cyl

Well at least to got it changed and it was the cheaper sensor.

Did you try a breaker bar or start the car and warm up the pipe to get it out? I had to use my foot to get enough power to break it loose.

 

[alphaae]

Well at least to got it changed and it was the cheaper sensor.

Did you try a breaker bar or start the car and warm up the pipe to get it out? I had to use my foot to get enough power to break it loose.

So for the backset of bolts on the exhaust pipe, I did have to run the car for about 15 minutes per bolt to break them. I did have a breaker bar for those to get them started.

As for the sensor I never got it out while still inside the engine. I tried using a propane torch on the actual pipe but when I used the special split socket to try and get it to lose I found myself tripping the bolt head which is what lead to the full pipe removal process.

 

[alphaae]

Adventure is smog continued.

Took the car for an oil change and retest for emissions.

So after the part change you need to do what's called a "drive cycle" for the sensor and computer to be able to make sure it's functioning right.

I'll touch bases back here in a few days once ive had a chance to drive it around.

 

[ravenuer]

Yeah, there's a certain drive cycle that has to be completed. I forget exactly what it was, but I think if you just use it as you normally would for a few days as you say. Let us know.