Denso o2 Sensor

[Paddo]

Okay, I got my 4Runner back today. The codes P0135 and P0141 are still there. They reassured me about a hundred times that the technician "did his best to fix the problem" but that they "wouldn't be able to tell for sure without new factory O2 Sensors."

EDIT:
I spoke too soon! The O2 sensor problem is still there, but even better... I got back into my car and noticed the 4WD shifter was over in the neutral position. I tried moving it around a bit before I realized they just forgot to hook it back up. I brought it back over to Toyota, and they told me all their techs had gone home and I'd have to bring it back tomorrow. Great. Another day without my 4Runner. I'm filing a complaint with Toyota. A really angry one.

 

[TheDurk]

Okay, I got my 4Runner back today. The codes P0135 and P0141 are still there. They reassured me about a hundred times that the technician "did his best to fix the problem" but that they "wouldn't be able to tell for sure without new factory O2 Sensors."

EDIT:
I spoke too soon! The O2 sensor problem is still there, but even better... I got back into my car and noticed the 4WD shifter was over in the neutral position. I tried moving it around a bit before I realized they just forgot to hook it back up. I brought it back over to Toyota, and they told me all their techs had gone home and I'd have to bring it back tomorrow. Great. Another day without my 4Runner. I'm filing a complaint with Toyota. A really angry one.

Those codes are Heater Circuit Malfunction codes in front and back sensors. I would check the heater resistance on both sensors as per attached. In your case, it applies to both sensors, although this FSM page is from the 2002 MY where it applies only to the rear.

If the sensors fail the heater resistance check, at least then you can change them with a clear conscience that it needed to be done. If they pass, I honestly don't know what to tell you. My guess would be new ones won't help, and then it is either the tech's fix was no good or your ECU is fried. Let's hope they fail.

The other possibility is that I am wrong, and new sensors will fix it even if your old ones test good. I just can't think why this is possible.

To verify the truckside fix by the tech is good, you could do the following:

In front, heater should be between a white wire with blue stripe (12V+) and a purple with blue stripe (ground via ECU) coming into the sensor connector. You should get 9-14V with ignition on.In the rear, same white with blue stripe for 12V+ and red with white stripe to the ECU. This assumes yours is the same as my '99, which I think it is. The 12V+ is full-time, the ground goes away with ignition off. If you don't get voltage across the two, then test each side separately, i.e. test between white/blue and battery ground and between battery positive and the other side on each sensor (with ignition ON).

 

[4'running'26]

[MENTION=10169]TheDurk[/MENTION], thanks for the pictures! I got around to checking again and I do indeed only have ONE cat. So, which of the two sensors should I start with? I could do both I guess, but I a trying to diagnose some mediocre gas mileage so I wouldn't mind doing one at a time to see if either of the makes a difference individually.

I also keep getting confused when looking for part numbers on these things. 2000 Toyota 4runner, Auto, one cat.

Thanks!

JT

 

[TheDurk]

[MENTION=10169]TheDurk[/MENTION], thanks for the pictures! I got around to checking again and I do indeed only have ONE cat. So, which of the two sensors should I start with? I could do both I guess, but I a trying to diagnose some mediocre gas mileage so I wouldn't mind doing one at a time to see if either of the makes a difference individually.

I also keep getting confused when looking for part numbers on these things. 2000 Toyota 4runner, Auto, one cat.

Thanks!

JT

Do the front first. The rear has no effect on MPG or performance. A bad heater on the sensor in front, P0135, will leave you in open loop, (start-up mode) and knock mpg's for a loop.

You need 2x 234-4162 as I posted above.

 

[4'running'26]

Thank you. Just ordered one from Amazon. $47. Not bad.

 

[JayRolla]

Was looking for o2 sensor and saw this post. Was going to make offer but seems a little overpriced. The oem sensor is same as the denso 234-4162. I dont think they cost $100.

 

[orbot]

damn it!!!

anyone here???

what the hell i got the p0420 light but both my sensors are in front of the cat, is this right???it drove fine, light came on a few months ago i turned it off, light came back recently like 10 days ago, so set up my not be making that big of a mess but it looks weird to me.
96 3.4 auto 4wd

thinking someone messed with it already, im the second or third or fourth or what ever damn number owner or the truck.

02 sensor, cat, 02 sensor, muffler thats it right??

 

[amalik]

From URD:



I have always found URD application data to be complete and reliable. Amazon, not so much.

(Note: the other engines also show 234-4162.)

Hey [MENTION=10169]TheDurk[/MENTION], reviving an old post here.

I'm in a bit of a quarrel and need some of your advice.

I have a 97, non-cali. (Side note: I don't think cali or non-cali matters for my 97. If I understood what you have said correctly in other posts, Cali VS non-cali only matters for 99 and 00 as the cali's got 2 cats in those years before the 01 fed standard).

Moving on .... I have a P0133, which is actually a Sensor *1* code (pre-cat, effects gas mileage), but I replaced the rear sensor in what I now realize was confusion on my part and not being thorough enough. I used Denso 234-4162 off Amazon.

Now here's my question.

URD website claims the following:

1996-1998 Auto 4WD V6 3.4; Front = 234-4162
1996-1998 Auto 4WD V6 3.4; Rear = 234-4154

As stated, I installed a 4162 into the rear, which is supposed to go in the front.

At this point, I'd like to throw another 4162 in the front to address the P0133, and simply keep the existing 4162 in the rear as opposed to yanking it and buying a 4154. Sensor 2 doesn't effect gas mileage anyway, from my understanding.

Would you advise against this? I find it strange 4162 was OK for front and back in 99 (per your quote), but different PN for 97 in the rear 2 years earlier.

And FWIW, I have no P0141 Sensor 2 code with the 4162 running in the back so far.

 

[TheDurk]

Hey [MENTION=10169]TheDurk[/MENTION], reviving an old post here.

I'm in a bit of a quarrel and need some of your advice.

I have a 97, non-cali. (Side note: I don't think cali or non-cali matters for my 97. If I understood what you have said correctly in other posts, Cali VS non-cali only matters for 99 and 00 as the cali's got 2 cats in those years before the 01 fed standard).

Moving on .... I have a P0133, which is actually a Sensor *1* code (pre-cat, effects gas mileage), but I replaced the rear sensor in what I now realize was confusion on my part and not being thorough enough. I used Denso 234-4162 off Amazon.

Now here's my question.

URD website claims the following:

1996-1998 Auto 4WD V6 3.4; Front = 234-4162
1996-1998 Auto 4WD V6 3.4; Rear = 234-4154

As stated, I installed a 4162 into the rear, which is supposed to go in the front.

At this point, I'd like to throw another 4162 in the front to address the P0133, and simply keep the existing 4162 in the rear as opposed to yanking it and buying a 4154. Sensor 2 doesn't effect gas mileage anyway, from my understanding.

Would you advise against this? I find it strange 4162 was OK for front and back in 99 (per your quote), but different PN for 97 in the rear 2 years earlier.

And FWIW, I have no P0141 Sensor 2 code with the 4162 running in the back so far.

If it fits and plugs up, you're fine. The ONLY difference there is wire length. Presumably it's too long rather than too short, but either way if it's working just leave it.

 

[SleepyRunner]

Hate to bring this up but I got a P0420 code and it won’t pass smog, it’s a 01 runner CA car. I was told I need a new cat due to being 300k, but I’m hopeing it’s the sensors, so what sensor do I need to replace? I believe being a CA car it has 2 cats, what are the part numbers again to order from amazon? I’m just so mixed up with the pass few pages. Any help will do thank you.

 

[mtbtim]

Hate to bring this up but I got a P0420 code and it won’t pass smog, it’s a 01 runner CA car. I was told I need a new cat due to being 300k, but I’m hopeing it’s the sensors, so what sensor do I need to replace? I believe being a CA car it has 2 cats, what are the part numbers again to order from amazon? I’m just so mixed up with the pass few pages. Any help will do thank you.

Watch this video and read the video description and it will provide you with everything you need to order the correct sensors and install them yourself.

<iframe width="560" height="315" src="https://www.youtube.com/embed/CtngAVxJxkE" frameborder="0" allow="autoplay; encrypted-media" allowfullscreen></iframe>

 

[SleepyRunner]

Watch this video and read the video description and it will provide you with everything you need to order the correct sensors and install them yourself.

<iframe width="560" height="315" src="https://www.youtube.com/embed/CtngAVxJxkE" frameborder="0" allow="autoplay; encrypted-media" allowfullscreen></iframe>

Thanks! Mtbim!

 

[bryantmorton99]

I need to replace my B1S1 sensor on my 2000 3.4 4WD automatic. How do I know if I need an o2 sensor or an Air and fuel ratio sensor?
EDIT: The truck was initially bought in New York, then was registered in Virginia (2004-2018) and now lives in North Carolina