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Denso 234-9123 Oxygen Sensor (Air And Fuel Ratio Sensor), Regular (2349123)

Brand: Denso

4.6 473 ratings

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$99.99 with 34 percent savings

List Price: $151.11

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Brand	Denso
Item dimensions L x W x H	5.75 x 2.19 x 1.88 inches
Material	Zirconium
Item Weight	0.3 Pounds
Style	Regular

About this item

Efficient Fuel Consumption
Constructed from durable material
Features zirconia solid electrolyte
Manufactured to detect the amount of exhaust gas air fuel ratio
Fit type: Universal Fit

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Powerbuilt Oxygen Sensor Offset Puller, Remove and Install O2 Oxygen Sensors, Wire Gate, 22mm 7/8 Inch, 6 Point - 648691

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CHOKING HAZARD -- WARNING: This product contains small magnets. Swallowed magnets can stick together across intestines causing serious infections and death. Seek immediate medical attention if magnets are swallowed or inhaled.

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Top Brand: Denso

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From the manufacturer

About us

DENSO is a global company focused on advanced mobility that positively changes how the world moves and contributes to greater well-being. As a global Fortune 500 company, we have a broad product portfolio and widespread global impact. We are focused on the development of core technologies in four fields to create new value and influence the future of mobility. DENSO's network spans across 35 countries and regions allowing us to share diverse perspectives and opinions to deliver global and regional solutions to meet societal needs.The DENSO brand is built on delivering more Quality and Reliability. Whether supplying the world’s automakers with reliable OE parts, or developing aftermarket, DENSO’s line of products are built to deliver superior all-around performance every day. At DENSO we’ve taken everything we have learned as an OE manufacturer and applied it to our aftermarket product lines. Every component that leaves our factories has been designed with precision, manufactured to OE standards. At DENSO, we’re constantly striving to break new ground with innovative solutions for today’s demanding automotive needs. All of our products are built to OE-standards and incorporate the upgrades — an OE manufacturer can make. DENSO First Time Fit products are manufactured to give you the right part and the right fit … the first time, every time.

Product Description

Denso Air and Fuel Ratio sensor is designed to detect the amount of the exhaust gas air and fuel ratio. It is constructed from durable material that is corrosion and abrasion resistant. This sensor features zirconia solid electrolyte integrated with alumina heater substrate which precisely controls the amount of oxygen concentration that flows into the diffusion layer to limit current flow. This sensor can easily be installed and ensures longevity.

Product information

Technical Details

Brand

‎Denso

Item dimensions L x W x H

‎5.75 x 2.19 x 1.88 inches

Material

‎Zirconium

Item Weight

‎0.3 Pounds

Style

‎Regular

Mounting Type

‎Threaded

Specific Uses For Product

‎Oxygen Sensor

Manufacturer

‎DENSO

Model

‎_

Item Weight

‎4.8 ounces

Product Dimensions

‎5.75 x 2.19 x 1.88 inches

Country of Origin

‎China

Item model number

‎2349123

Is Discontinued By Manufacturer

‎No

Exterior

‎Machined

Manufacturer Part Number

‎234-9123

Additional Information

ASIN

B001F7EK44

Customer Reviews

4.6 473 ratings

4.6 out of 5 stars

Best Sellers Rank

#86,417 in Automotive (See Top 100 in Automotive)
#207 in Automotive Replacement Oxygen Sensors

Date First Available

January 2, 2007

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Amazon.com Return Policy:Amazon.com Voluntary 30-Day Return Guarantee: You can return many items you have purchased within 30 days following delivery of the item to you. Our Voluntary 30-Day Return Guarantee does not affect your legal right of withdrawal in any way. You can find out more about the exceptions and conditions here.

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	This Item Denso 234-9123 Oxygen Sensor (Air And Fuel Ratio Sensor), Regular (2349123)	Recommendations DrCax Oxygen O2 Sensor Heated Air Fuel Ratio Upstream 234-9123 Compatible with Subaru 06-09 Outback Legacy 06-10 Forester 06-11 Impreza Sport 2006 SAAB 9-2X 2.5L-H4 Replace 22641-AA360	dummy Marsflex Air Fuel Ratio O2 Oxygen Sensor Upstream 234-9123 Compatible with Subaru Legacy Outback Impreza Foreste Saab 9-2X H4 2.5L Replacement 15171 22641-AA33A	dummy TINJO Oxygen O2 Sensor 234-9123 Upstream & Downstream 234-4445 Compatible with Subaru Legacy Outback 2006-2009, Fit for Impreza 2005-2011, Forester 2005-2010, Saab 9-2X 2006 2.5L Oxygen Sensor - 2pcs	dummy Offset Oxygen Sensor Socket, 3/8-Inch Drive, 7/8-Inch (22mm), Wire Gate Accesses Sensor from Side, Preventing Damage to Wires, Universal for Most Cars	dummy Denso 234-5053 Oxygen Sensor (Air and Fuel Ratio Sensor)
	Try again! Details Added to Cart	Try again! Details Added to Cart	Try again! Details Added to Cart	Try again! Details Added to Cart	Try again! Details Added to Cart	Try again! Details Added to Cart
Price	-34% $99.99 List: $151.11	$43.99	$36.99	$69.89	$6.99	-38% $97.78 List: $158.45
Delivery	—	Get it as soon as Friday, May 10	Get it as soon as Friday, May 10	Get it as soon as Friday, May 10	Get it as soon as Friday, May 10	Get it as soon as Friday, May 10
Customer Ratings	4.6473	3.9195	4.02,978	3.02	4.4924	4.5214
Easy to install	4.5	4.0	4.1	—	3.8	4.3
Value for money	4.5	3.4	3.5	—	3.8	4.5
Mileage	4.3	3.5	3.1	—	3.6	4.7
Sold By	Amazon.com	DrCax Store	Marsflex	Hispeemotor	YOGEIER	Amazon.com
specific uses	Oxygen Sensor	—	—	—	Molybdenum	Oxygen Sensor
material	Zirconium	—	—	Stainless Steel, Aluminum Oxide	Steel	Zirconium
mounting type	Threaded	Flange Mount	Flange Mount	Flange Mount	Flange Mount	Threaded
style	Regular	—	Upstream	—	Compact	Modern

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Customer reviews

4.6 out of 5

473 global ratings

How customer reviews and ratings work

Customers say

Customers like the performance, quality, fit and value of the electronic sensor. For example, they mention it works well, is of high quality, fits perfectly and is easy to install. Some appreciate the value for money. That said, some are happy with ease of use.

AI-generated from the text of customer reviews

37 customers mention35 positive2 negative

Customers are satisfied with the performance of the electronic sensor. They mention that it fits well, works well, and clears computer error codes. Some say that the product is reliable and has no issues. Some customers also mention that the gas mileage increased a bit and performance is what they would expect.

"...It has performed with no problems." Read more

"...There have been no error codes, fuel mileage is what I would expect and the engine runs great.Update...." Read more

"...bad really messes up the fuel mixture- makes car run rich, so gas mileage is better and it runs way better, more power etc...." Read more

"...No issues at all I would definitely recommend this product." Read more

24 customers mention17 positive7 negative

Customers like the quality of the electronic sensor. They say it's a well-built part, and an OEM original part. Some customers also mention that the engine is still running strong after two years, and there's no check engine light.

"...Update. Almost 2 years later the engine is still running strong, good fuel trim, no sensor-related check engine light...." Read more

"...Installed this one, cleared computer, and it ran great. No more trouble code." Read more

"...Horrible job. 2009 forester." Read more

"works for 2008 Subaru Impreza CEL went away. Quality material and it fits !" Read more

22 customers mention22 positive0 negative

Customers are satisfied with the fit of the electronic sensor. They mention that it fits perfectly as the connector is identical to the OEM one, and it's a direct fit plug and play for the 2006 Forester 2.5.

"...Since it is OEM, it fit perfectly, and the cable clips were in exactly the right spots. It has performed with no problems." Read more

"it fit perfectly as far as the connector was identical oem. you want to only go with denso which is the oem supplier for subaru...." Read more

"Perfect fit in my 2006 Forester X. Matched OEM part exactly, down to the clip, plug, even insulator color...." Read more

"Perfect fit!! Easy to install once old one is removed...." Read more

11 customers mention11 positive0 negative

Customers find the electronic sensor easy to install and work on. They say it makes the job even easier.

"Perfect fit!! Easy to install once old one is removed...." Read more

"...Makes the job even easier. I put up with my Subaru's quirks because it's so easy to work on." Read more

"Worked great, easy to install with a crow’s foot Oxygen sensor tool bought on Prime or Harbor Freight. Save $100 and do this yourself." Read more

"This installed very easily. Engine Check light turned off." Read more

10 customers mention10 positive0 negative

Customers appreciate the value of the electronic sensor. They say it's a good deal and a great buy on OEM part.

"...price from this vendor is great, best i have seen anywhere. new at oreilly etc was $50 more cost!..." Read more

"...Direct swap for OEM on my daughters 2010 Forester. Great price and quick delivery...." Read more

"...Didn't work. Replaced with Denso and works great. Awesome price verses OEM." Read more

"Cheap and plug and play, got rid of my check engine light" Read more

7 customers mention7 positive0 negative

Customers find the electronic sensor easy to install. They say it matches up and plugs right in. Some mention that the sensor makes changing the sensor much easier.

"...Downstream sensor was super easy. This one however took 3 hours. Old one was super stuck. Crows foot tool was useless just rounded the hex...." Read more

"Fit as it should, plugged right in no problem, good replacement part" Read more

"Cheap and plug and play, got rid of my check engine light" Read more

"...The sensor is completely plug and play and the price is great compared to the dealer and local auto parts stores. I couldn't be happier." Read more

4 customers mention4 positive0 negative

Customers are satisfied with the check engine light feature of the sensor. They mention that it works well and turns off the check light.

"...The sensor has worked well-no check engine light, and the scanner showed fast response and good fuel trims...." Read more

"This installed very easily. Engine Check light turned off." Read more

"...without hassle, connected battery terminal, turned car on, no more check engine light, smooth operation. Subaru Impreza 2006...." Read more

"Worked perfect exact fit. Check engine light is off and car runs much better." Read more

4 customers mention2 positive2 negative

Customers are mixed about the connectivity of the electronic sensor. Some mention that they didn't need to splice any wires, while others say that the connector is different and the plug isn't a match.

"...Whole install took her about 20mins and had no need to splice any wires. Hope this helps!" Read more

"...my local parts store to check it-the numbers match but the connector is different. Perhaps there was a change made after my car was made...." Read more

"The wires were just perfect unlike some aftermarkets" Read more

"Plug isn't a match 2007 Subaru Outback 2.5L..." Read more

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Kyuzo

OEM Quality

Reviewed in the United States on April 23, 2024

Verified Purchase

I installed this sensor on my Subaru as part of regular maintenance. Since it is OEM, it fit perfectly, and the cable clips were in exactly the right spots. It has performed with no problems.

Helpful

Fred Oliver

A good deal on OEM sensor for a Subaru.

Reviewed in the United States on September 11, 2017

Verified Purchase

I bought this as an upstream sensor for 2007 Subaru with a 2.5 liter engine to replace an original after 225,000 miles. It came with some copper anti-seize compound. It looked like the original with one important exception-the wire connector was different than the original one in my car. I checked the part number several times, and even ordered another one from my local parts store to check it-the numbers match but the connector is different. Perhaps there was a change made after my car was made. Because I needed to get my car back together, I cut the connectors off and swapped my original onto the new sensor-the wires are the same, so it was just a minor challenge, but cutting into an expensive part made me nervous. The sensor has worked well-no check engine light, and the scanner showed fast response and good fuel trims.
After almost 6 months and more than 10,000 miles, this is still working. There have been no error codes, fuel mileage is what I would expect and the engine runs great.
Update. Almost 2 years later the engine is still running strong, good fuel trim, no sensor-related check engine light.
Update. I got another one of these for another car, and in the process learned why I thought the connector was wrong. It has a plastic protective piece that I thought was part of the connector itself. Removal of the piece revealed the correct connector. That was a critical thinking problem on my part, and realizing the error of my ways has hopefully made me a better person in some small way.

17 people found this helpful

Helpful

John B. Rogers

Go only with Denso- oem supplier to subaru

Reviewed in the United States on October 29, 2017

Verified Purchase

it fit perfectly as far as the connector was identical oem. you want to only go with denso which is the oem supplier for subaru. price from this vendor is great, best i have seen anywhere. new at oreilly etc was $50 more cost! ck engine lite went out immed, car runs so much better as this going bad really messes up the fuel mixture- makes car run rich, so gas mileage is better and it runs way better, more power etc. this is the upstream 02 sensor, which is the one that takes the worst beating of the two 02 sensors in any vehicle. it should be replaced about every 80k miles, the downstream one can go longer. funny but my ck engine lights just got thrown, runs fine but something threw that, could be downstream sensor but car only has 90k miles so it should not be going bad this soon. supposed to go like 150k or more even because its downstream of the catalytic converter so it gets cleaner air and doesnt go down as fast as upstream which gets raw untreated exhaust. i did a ohm test on downstream and it was in spec, i did upstream prior to replacement and it was showing out of spec. ck engine analysis cemented the fact it needed replacement at about 90k mi, but actually the lite was throwing at about 84k. newer subarus are more sensitive to sensors, mine is a 2010. 2008 and older are not nearly as effected by sensor health as 2009 and newer.

One person found this helpful

Helpful

This does work with a Subaru unlike the Chinese brands

Reviewed in the United States on February 28, 2024

Verified Purchase

If you have a Subaru that needs a new air fuel sensor or front oxygen sensor this would be the one to go for this will turn your engine light off as long as the sensors the issue unlike the Chinese replacement sensors which will give you issues with the heater circuit worth the price cuz they actually work do yourself a favor if you're going to replace your sensor do it with a Denso on a Subaru

One person found this helpful

Helpful

DesolationRow

so if an offset O2 sensor socket doesn't break it loose pretty easily, just pull the headers

Reviewed in the United States on April 26, 2016

Verified Purchase

Direct replacement for 2006 Impreza (and many other models and years). First one leaked air through the stem right out of the box. Amazon took the return no problem.

Some installation tips: getting the old one out is the hardest part. They often get really baked in there. Removing the headers isn't that hard, so if an offset O2 sensor socket doesn't break it loose pretty easily, just pull the headers. If the old one comes out easily then this one should go in easily. If the old one needed a lot of persuasion, it would be smart to get a thread chaser and clean out the female threads before trying to thread this one in.

Once it's installed, tape a shop vac hose on "blow" into the tailpipe to build up a little pressure in the system and spray any joints you messed with (o2 sensors, headers) with soapy water. Bubbles = leaks.

2 people found this helpful

Helpful

Amazon Customer

Factory part subaru uses

Reviewed in the United States on February 11, 2024

Verified Purchase

This is what subaru uses in their cars aftermarket parts that are cheaper don't usually work properly in a subaru or they work temporarily and you end up buying the original part. Still 50 to 60 dollars cheaper than buying locally for the same part

Helpful

S. Chanchanian

Swapped out easily, fixed 420 error code!

Reviewed in the United States on January 29, 2024

Verified Purchase

Car started throwing 420 cat converter code, which this solved immediately. This was very easy to swap out, literally unplug and unscrew old sensor, and plug in new one.

Helpful

PacNWLady

OEM is still the better choice

Reviewed in the United States on January 21, 2024

Verified Purchase

While the aftermarket does provide a good amount of products as replacement parts. There are still some area’s that the OEM replacement parts are the only choice to use. This comes from personal experience in the automotive industry as a mechanic.

Helpful

Top reviews from other countries

Amazon Customer

OEM part.

Reviewed in Canada on May 3, 2023

Verified Purchase

Replaced the front A/F sensor with this OEM part, fit perfectly and works perfectly, spend the extra to have a quality name brand, I had previously purchased a non name brand, trying to save some cash, it lasted 1 week, it looked the same until I actually measured the 2 sensors, the no name was actually longer, and the car kept throwing codes, once replaced with the Denso sensor, no more codes

The Master

Great product/quality price - prompt shipping

Reviewed in Canada on August 5, 2019

Verified Purchase

Great product/quality price - prompt shipping

Earl Woolery, III

OEM Fit and Quality

Reviewed in Canada on September 27, 2022

Verified Purchase

Exact replacement fit perfectly and no issues once installed.

Danny d

Strait oem replacement

Reviewed in Canada on March 28, 2021

Verified Purchase

Worked well for my 06 suburu impreza 2.5i

Superfeet1011

Exact Fit 2009 Subaru Forester

Reviewed in Canada on September 25, 2022

Verified Purchase

This is an exact fit for my 2009 Subaru Forester. My Check Engine light is gone. I’m very happy with this product!

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Denso 234-9123 Oxygen Sensor (Air And Fuel Ratio Sensor), Regular (2349123)

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