Denso o2 Sensor

If I were you, I would look at the plug on your existing sensor. The A/F are different, specifically the ridges on one side. This is the 234-9002:

234-9002


This is the 234-4162.

234-4162




Notice the ridges go 3-0-1-2 on the A/f (counting from top going clockwise) and the O2 goes 3-2-2-0.

Go with what plugs into your truck. (See!,...both have 4 wires.)
 
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And the 9002 is for the CA truck correct? I will look at it in the morning. Right now it is to hot out and the truck is still warm also.

Blue
 
And the 9002 is for the CA truck correct? I will look at it in the morning. Right now it is to hot out and the truck is still warm also.

Blue

For the 2000 V6 Auto trans Cali.'s, yes. 5-speed and 4-cyl are different. Plug will be the same, but wire length will be different.

By the way, if your truck is like my '99 Cali. 5-speed, the only way to get to the front plug is remove the sensor first and pass it over the top and let it hang down the other side. Good luck.
 
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If I were you, I would look at the plug on your existing sensor. The A/F are different, specifically the ridges on one side. This is the 234-9002:

234-9002


This is the 234-4162.

234-4162




Notice the ridges go 3-0-1-2 on the A/f (counting from top going clockwise) and the O2 goes 3-2-2-0.

Go with what plugs into your truck. (See!,...both have 4 wires.)

Thank you for this. Hopefully one of my plugs looks like either of those.
 
Well balls I have the AF. I only say that because it's $100, while the O2 is $50. Thanks again for the help. Ugh my wallet is getting smaller.
 
Well balls I have the AF. I only say that because it's $100, while the O2 is $50. Thanks again for the help. Ugh my wallet is getting smaller.

I guess your hood is not original or the factory screwed up. No one in their right mind would retrofit the Cali' system. My '99 Cali. says "CAL & OTC" where yours says "FED & CANADA" at the bottom and the paragraph is all "ok to be sold in California." Definitely a Fed 49-state label.
 
Pulled it to check

So I got under the truck this morning and made sure. Sure enough you are correct Sir.

Thanks again, parts ordered today.

Blue
 

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If I were you, I would look at the plug on your existing sensor. The A/F are different, specifically the ridges on one side. This is the 234-9002:

234-9002


This is the 234-4162.

234-4162




Notice the ridges go 3-0-1-2 on the A/f (counting from top going clockwise) and the O2 goes 3-2-2-0.

Go with what plugs into your truck. (See!,...both have 4 wires.)

Hi,

Is there any instruction about how the gasket gets installed? The two sides seem slightly different. Can"t remember how it was when I removed it.

Thank you.
 
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Hi,

Is there any instruction about how the gasket gets installed? The two sides seem slightly different. Can"t remember how it was when I removed it.

Thank you.

Honestly, I've never seen it written down, and it's been 50k miles since I've done one. I think the side with more metal goes up (away from the pipe), but I would accept correction from anyone who has done it recently. I also have no idea if it makes any difference.
 
Good lawd all this o2 sensor crap is confusing :confused: lol damn now I've gotta know what I've got! :what:

Sent from my DROID4 using Tapatalk 2
 
Wanted to bring this back to the top to make sure there wasn't anything new and exciting I was missing.

Have a CEL on... '99 4R, 4wd, auto. Planning to replace both o2 sensors with the Denso units purchased through amazon.

Thanks!
 
This is super confusing! Just read through all the posts. Here's the cliff note version.

Get under your car and count the number of cats.
While you're under there, spray everything with PB blaster.
Look at the sticker under your hood for federal or CALI emissions
Look up the correct part numbers on denso or URD website.
Go to amazon and order!

I have a '99 Auto, 4wd, PA vehicle that has 2 cats and CALI emissions. Ordered the 234-9002 (Front) $104.01 and 234-4153 (Rear) $56.86 from amazon. Both purchased through amazon prime, free 2 day shipping. So once we get back from Home Depot and Bed Bath and Beyond, maybe, I'm not sure, if we have enough time, I'll spend Saturday afternoon hopefully getting rid of the CEL!

While at HD saturday morning I'll buy 4x M8-125 nuts per someones earlier post because mine are all rusted and I'm sure will break when trying to remove them.

Hopefully I got the right stuff!
 
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This is super confusing! Just read through all the posts. Here's the cliff note version.

Get under your car and count the number of cats.
While you're under there, spray everything with PB blaster.
Look at the sticker under your hood for federal or CALI emissions
Look up the correct part numbers on denso or URD website.
Go to amazon and order!

I have a '99 Auto, 4wd, PA vehicle that has 2 cats and CALI emissions. Ordered the 234-9002 (Front) $104.01 and 234-4153 (Rear) $56.86 from amazon. Both purchased through amazon prime, free 2 day shipping. So once we get back from Home Depot and Bed Bath and Beyond, maybe, I'm not sure, if we have enough time, I'll spend Saturday afternoon hopefully getting rid of the CEL!

While at HD saturday morning I'll buy 4x M8-125 nuts per someones earlier post because mine are all rusted and I'm sure will break when trying to remove them.

Hopefully I got the right stuff!

Do tell. Did you have the right parts? I need to replace at least the front in my 99
 
Hello everyone.
I hate to resurrect an old thread, but hopefully this will be a simple question:

I have had two codes for some time - P0135 and P0141 If I remember correctly. It is a 2000 4Runner Limited 3.4L, 4WD, NON-California spec. exhaust. There is only one cat. My car is at the dealership right now for another repair. They told me the problem was a bad connection somewhere in the wire, and it had shorted out my O2 sensors.

I asked them to fix the wiring, but leave the O2 sensors alone because they wanted to charge me $200 for one, and $300 for the other. After checking several websites, it appears the part number I need is 234-4162. According to Denso's website, it looks like these are the same part. (this part on Amazon - a much better deal than what the dealership wanted).

Is that correct? Should I order two of the same O2 sensor? If that's the case, why would the dealership be charging me something different for each one?

Thanks
 
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That's correct. Per Find My Part | DENSO Auto Parts

Z32xC2u.png


Presumably the book labor hours are different depending on the location. Part price should be the same. Front sensors are probably more time.

I'm not sure how a short could damage a sensor. It just wouldn't work while the short was present. See if it works when you get it back. There might be nothing wrong with them. Just reset any codes and see if they come back. Post the codes then. I wouldn't put it past your average stealer to up the revenue on the job by saying they had to change the sensors when they didn't.
 
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So, if I only have one cat. do I have two sensors, or one...or is it one O2 sensor and one A/F sensor?

After trying to bring my fuel mileage back up into the 20s during all-hwy trips through other methods (ie. plugs, wires, pcv, air filter, resetting ECU-which always used to work but doesn't now) I might try the O2 sensor/sensors.

And lastly, as stupid as I feel asking this question, if I had two cats, would they both look the same? My luck, I would buy the parts only to find out, "oh, that is a catalytic converter as well, it just looks totally different than the other one." So to be sure...if I had two, what would the second one look like, and where would it be positioned? Directly in line with the first?

Thanks!

Here's a quick pic I snapped...might not have gotten the best view of it though.

 
I'm not sure how a short could damage a sensor. It just wouldn't work while the short was present. See if it works when you get it back. There might be nothing wrong with them. Just reset any codes and see if they come back. Post the codes then. I wouldn't put it past your average stealer to up the revenue on the job by saying they had to change the sensors when they didn't.

That's exactly what I was thinking. I'll clear the codes again if there are any when I get it back. I asked them to just try to fix any damaged connections and they kept giving me a line about how they wouldn't be sure it would be fixed without new sensors, but they'd do their best.

Thank you for the info., though. I appreciate the help. I just wanted to be sure that if I do end up needing to replace the sensors, I have the right ones.

I should have it back tomorrow morning, so I'll try to keep you posted.



Also, 4'running'26:

So, if I only have one cat. do I have two sensors, or one...or is it one O2 sensor and one A/F sensor?

After trying to bring my fuel mileage back up into the 20s during all-hwy trips through other methods (ie. plugs, wires, pcv, air filter, resetting ECU-which always used to work but doesn't now) I might try the O2 sensor/sensors.

And lastly, as stupid as I feel asking this question, if I had two cats, would they both look the same? My luck, I would buy the parts only to find out, "oh, that is a catalytic converter as well, it just looks totally different than the other one." So to be sure...if I had two, what would the second one look like, and where would it be positioned? Directly in line with the first?

Thanks!

Here's a quick pic I snapped...might not have gotten the best view of it though.


As far as I know (and I'm no expert) if you have just one cat there will be just two O2 sensors. One is upstream, before the cat, and the other is downstream, after the cat. The purpose of having two is to compare the exhaust gases before and after the catalytic conversion to make sure your cat is functioning efficiently.

I think only the California spec exhaust systems have an A/F sensor. Also (and I'm not totally sure) I believe if there is a second cat, it will be smaller and more round, and toward the front of the vehicle from the one in your photo. I think on some of the later models (4th gens) there were two sets of exhaust pipes, each with a catalytic converter and a bank of two sensors. Maybe that was just the V8's? Anyway, hope this helps.
 
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So, if I only have one cat. do I have two sensors, or one...or is it one O2 sensor and one A/F sensor?

After trying to bring my fuel mileage back up into the 20s during all-hwy trips through other methods (ie. plugs, wires, pcv, air filter, resetting ECU-which always used to work but doesn't now) I might try the O2 sensor/sensors.

And lastly, as stupid as I feel asking this question, if I had two cats, would they both look the same? My luck, I would buy the parts only to find out, "oh, that is a catalytic converter as well, it just looks totally different than the other one." So to be sure...if I had two, what would the second one look like, and where would it be positioned? Directly in line with the first?

Thanks!

Here's a quick pic I snapped...might not have gotten the best view of it though.


All the trucks have two sensors. The two-cat systems use an A/F in front and O2 behind, and the one-cat systems have two O2's. On two cat systems, the front cat is right at the bend bend upwards to the manifold, so I can't tell from that picture. It looks different from the rear cat. These are pics of a two-cat system.
 

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