Denso Primary O2 Sensor
Part Number: 234-9005
Inside Continental United States
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Will It Fit Your Vehicle?
This Denso O2 sensor is the wideband air/fuel sensor that you need for your 02-04 Acura RSX (DC5), 02-05 Civic Si (EP3), and 02-04 Honda CRV. This is also the primary 02 sensor needed for Hondata KPro for the 05-06 Acura RSX.
Don't be fooled by the much lower prices from other websites that tell you their sensors come in a Denso box but may have been manufactured by someone other than Denso - that simply means you are not purchasing an authentic Denso sensor and are overpaying for a Denso box. K Series Parts only sells real Denso sensors in Denso packaging.
This sensor is a direct replacement for the Honda/Acura parts: 36531-PRB-A01.
This Denso oxygen sensor is direct plug and play so no cutting or wiring is required for installation.
DENSO's light duty oxygen sensor started to appear on vehicles with the development of fuel injection systems. The basic job of the sensor is to monitor the air fuel mixture under idle, moderate acceleration and cruise conditions. Under heavy acceleration the oxygen sensor goes into "open loop," which basically means that the engine management computer system ignores the oxygen sensor. Oxygen sensors have a smaller range of limits in detecting and adjusting the difference from an optimum air/fuel ratio.
As the automotive industry continues to improve on their standards DENSO is keeping the pace with advancements in our engineering to meet the demands from the industry. Also, as car owners are holding on to their vehicles for longer periods, DENSO continues to make auto parts available for those critical replacement parts for all applications.
Oxygen sensors, also known as Lambda sensors or O2 sensors among some vehicle manufacturers, are among the most sensitive and critical components on your car's engine. Earlier fuel injection systems employed one oxygen sensor in the exhaust system to maintain closed-loop air/fuel mixture control. However, today's engines may use as many as four sensors, which monitor not only exhaust gas oxygen content but catalytic converter efficiency as well. In order to perform these functions properly, the sensors must adhere to OE standards within incredibly close tolerances. A malfunctioning or incorrectly calibrated oxygen sensor can hurt driveability and illuminate the malfunction indicator, resulting in costly and time-consuming repairs. DENSO First Time Fit® oxygen sensors are designed to meet those tolerances and more. The DENSO oxygen sensor catalog offers one of the most complete product lines in the industry, from Acura to Volvo.
- Corrosion-resistant stainless steel construction
- PTFE filter blocks efficiency-robbing contaminants
- Refined zirconia element improves sensor response
- Superior design maximizes engine performance and fuel efficiency while reducing fuel consumption and harmful emissions
- First Time Fit® delivers the right part the first time
- Ensures smog test compliance
62 reviews for Denso Primary O2 Sensor
4.967741935483871 out of 5.0
12/9/2015 by Sheldon Fernandez
good for its price
Cleared my CEL light.works so far,as it should. Great product thus far
2/9/2015 by aferdiansyah
cleared P1166-P1167 code
As described and great fitment. Replace with this product and no more code and engine running smooth with much better gas mileage. Worth the price. Thank you!
11/13/2014 by valter pedreira
Good by CEL
Installed on a 2002 rsx type s,fitment was great,quick shipping great price.Saved big $$$$ compared to dealer price
9/18/2014 by Algenis Gandarilla
what u pay for , is what u get !
Installed on my 2004 civic si ep3 after diagnosting it had a bad 02 sensor, CEL came off right after install. Car feels a lot more smoother at idle , gas mileage got a bit better, definitely worth the $$, Kseriesparts has the best deals and I will definitely continue to buy from them
7/4/2014 by David Moller
Took care of my CEL
CEL light would turn on. And my rpm would go too low when car @ stop. Just a littl push of gas and it would stall. It would go away when i open the fuel cap. But withing few days it would come back on. Eventually after a few months. It just stayed on. After getting a free read @ local autoparts & from reading @ few forums. Idecided to replace this sensor. Its pretty easy just raise the car from passenger side high enough.Took off the side skirt to make it a little easier. Having the O2 sensor rem. socket also helps but not necessary. Car runs great now. Super fast shipping!
12/22/2013 by Bunly Heng
needed it because my primary o2 was going bad and after the installation it fixed my CEL.
10/3/2013 by lucas ronk
had CEL put this in and no CEL
6/28/2013 by Stefan Arsen
Fixed my Car
my car rpms would near drop to 100 on red lights and almost stall. This sensor fixed everything and p1167 and p1166 went away, and my car runs a lot more efficiently and faster.
6/13/2013 by Nicholas Mersing
Ordered a Kpro for my 2006 Acura RSX-S , this is a must have for any 05-06 RSX-S when using Kpro! Fast shipping, good quality, works great!
5/5/2013 by DJ Showbot
Had the CEL for like two years and finally needed this sensor to clear emissions. Worked like a charm. Whatever they do over there at Kseries works, because they always have super fast shipping.
1/3/2013 by Tony G Conception
Honda Quality Primary O2 Sensor
This was the same sensor I pulled out of my car quality was great and it even had the extesion to fit my ep3 swap . Price is also better than anyone elses after i shoped around
12/15/2012 by Allen
A necessity for upgraded modifications. Perfect fit and works well. K-Series customrr service is one of the Best!
12/11/2012 by Matt
perfect fit, fast shipping. check engine lights gone. definitely worth the money dont bother with the cheap ones.
9/8/2012 by Shane
Both parts came quickly and were as i ordered.
6/28/2012 by Fred Manigat
Check engine light was on for more than a year now and as soon as I got it put it on and cleared the codes and like magic that yellow engine was gone :)
5/11/2012 by justin
got this the other day installed it and then cleared the code and it hasnt been back since!!!!!!! GOODBYE CEL!!!!!!!!
5/5/2012 by Melvin Gutierrez
denso sensor so much better
easy installation part came in super fast very satisfied customer! thanks k series parts!!
4/29/2012 by Joe
Denso OE Replacement Primary O2 Sensor
It was easy to install and the check engine light went off after i disconnected my battery and reconnected it. The removal of the stock 02 sensor can give you a lot of trouble. Great product for a great price.
3/23/2012 by Troy
Super fast shipping and worked like a charm!!!
I finally broke down and jumped on this O2 sensor due to the price. ClubRSX has this at my door BEFORE expected and it cleared my CEL. Awesome OEM part and EXCELLENT customer service from CRSX.
3/22/2012 by javier betancourt
Turn that damn CEL off thanx.
2/16/2012 by Jason
Turned my engine light off.
2/15/2012 by Joseph
Product came in fast, and works great! Now getting the mileage I should.
12/9/2011 by michael tessari
SWEEET No Check Engine light
Plug and play, works great.
10/6/2011 by Geneva
This part is just what I needed and at the perfect price! Couldn't find a cheaper part anywhere and I even work for Honda! The O2 sensor was shipped fast and I received it just a couple days after placing the order. Definitely recommend ClubRSX and this part. I will never purchase another part anywhere else.
9/30/2011 by Johnny V
Had DTC P1166/P1167. Cleared MIL and installed O2 sensor. Works great!! Good price and super fast shipping!!!
8/30/2011 by Joel Goldberg
Identical replacement. PITA to take off the old one. Five minutes to attach the new one. Code goes away, engine runs smoother, mileage goes up slightly.
6/24/2011 by Kevin
Fast delivery, replace'd old o2, works perfectly fine with my 05-s kpro'd. Simply does it's job
5/8/2011 by Kris
denso primary o2 sensor
Great product!!! CEL code is gone for good. No check engine light!!! Easy 5 minute install!!
5/3/2011 by Justen
denzo o2 primary sensor
great product!!!!!!!! car responds way better, gas mileage is way better and it took out my check engine light!!! thanks crsx!
3/16/2011 by Clint
Awesome O2 Sensor!!!
Just installed last week and pairs perfectly with the Kpro system on my 06 RSX. Had no problems on install or daily driving. Works Great!!
3/9/2011 by John Zimmerman
This product is amazing. Point blank.
12/29/2010 by Mike
Check engine light
Code went away and car runs much better! Very easy to change too.
10/26/2010 by Chaul Lee
Denso OE Replacement Primary O2 Sensor
Great item!!! Fast shipping!!! Works great!!! Thank you!!!
10/21/2010 by Lan Tran
Easy to install!
Ordered this when my primary O2 sensor went out, only took 20 minutes to install. Make sure you get the O2 sensor removal tool! Car has been running great since the replacement. :)
10/5/2010 by Martin Torres-Green
Fast shipping, worked great, great price.
7/19/2010 by Jeff
replaced the sensor with ease... but after i tried to clear the codes it showed i now need the secondary one too. California smog laws suck. good product though still.
7/1/2010 by andre
It works fine as a replacement
It works fine as a replacement at first installation. Don't know how long it would last so I cannot rate full.
2/4/2010 by Steve
Replaced sensor to remedy codes
After receiving the dreaded 'check engine light' I checked the codes with a code reader. They were two related to the secondary O2 sensor - slow or no response; heater failure. Replaced the sensor (make sure you get the tool from Autozone to get it out of the cat easily, it's in a recessed area, but you can see where the wires head in near the engine side of the cat) and the codes are gone. Be careful when you hook the wiring back up, mine came loose and had to be reconnected a second time. Whoops! The sensor seems fine (I mean, it is the original equipment) and the original lasted from 2003 to late 2009, 6 years ain't bad I guess.
1/11/2010 by Ibrahim Moreno
THE SENSOR WORK WELL ON MY VEHICLE AND IT TOOK CARE OF THE RPM NEEDLE FROM GOING UP AND DOWN.
12/20/2009 by Michael J. Muldowney
A trip to Advance Auto to get the codes, diagnosed cel w/ dealer manual found online. Took a few evenings to diagnose with a multi since I'm a novice. But, took 20 min to remove old sensor and drop in this one in a parking lot with a "curb hop". Saved a few hundred by avoiding dealer/mechanic on this one.
11/10/2009 by Justin Fincher
Can't beat the price, mine went out when I installed the OBX (v2) Raceheader on my EP3 and the o2 CEL code went out immediately. The extra length (for it being made for the RSX) gave it some slack as well :P Thanks a ton CRSX!!!
10/10/2009 by George
Great price, fixed the problem.
Priced well, was easy to install. Fixed the problem I had, the light didn't come back on.
8/26/2009 by kenny
quick shipment on this item... pretty easy to install with the appropriate 02 sensor removal tool
8/13/2009 by Berto
Got rid of my P1166 and P1167 codes
Sup guys this sensor is at a good price so don't look anywhere else. Had the check engine light on on my K20A2 and this sensor was the solution to codes P1166 and P1167. See u in the forums.
8/5/2009 by Jordan
Great price, great product!
I got a cel as soon as i installed my raceheader, te primary was bad. Bought this sensor, it was at the best price i could find. The light has never come back!
7/24/2009 by Dennis
Fast shipping and great price
I was looking for this sensor and this was the lowest price I found from a legit site.
6/11/2009 by Eric
Had no problems at all installing this sensor and it works great.
5/16/2009 by Aaron
Couldn't be more pleased
The 02 sensor was a great price, came in quick, and was a direct replacement so really, I couldn't ask for anything more except: CRSX may want to offer an 02 removal socket so those who don't have one could get them at the same time. US 02 sensor sockets are easy to come by, but it's harder to find the correct metric one in the typical Autozone type stores.
3/31/2009 by Nicholas Gernt
Buy it here...
I looked around for a replacement primary sensor and either none were available or they were too much $. Trust me, buy it here, the price is the best you will find, shipping was ultra fast (3 days to get to Massachusetts) and clubrsx is easy to work with. I shopped around for a while trying to find a better deal and it was just a waste of time. Other than that, the sensor works perfect. I've put a little over 2k on my car since installing the sensor and the CEL hasn't even blinked once at me. The engine runs smooth again and my gas mileage is back where it should be.
3/31/2009 by Steve Trask
not just for the type s!
I have a base auto, and figured I would try out this sensor, since the one for the base auto was back ordered. I am happy to say it works great! fitment is good, the connectors are the correct length, and best of all my gas mileage doesn't suck anymore!
3/28/2009 by T-DOT
oe denso o2 sensor
Great working quality sensor and the best price ever!!!
3/13/2009 by fcrsxtypes
denso 02 sensor
1/6/2009 by rob
oe denso sensor
Great product direct fit no cutting or splicing. Save yourself the headache buy this if you are looking for a primary o2 sensor for your dc5
12/1/2008 by Stephen Malone
My Primary 02 sensor went bad not too long ago. I ordered this one through club rsx and received and installed in less then a few days. Easy install on my race header. Simple unplug and replug. CEL is gone and my gas mileage has gone up a good bit. I recommend Denso.
11/24/2008 by Joel
I got a CEL and determined that I needed to replace the Primary O2 sensor. Like others here I first tried to order from a couple of online stores that claimed to have it in stock but actually didn't. In fact, one tried to sell me a more expensive off-brand sensor after taking my original order. I canceled those orders and found it here at Clubrsx--for a better price to boot. Installation was easy with the right tools and my CEL is gone.
11/23/2008 by kidinatype_s
02 for my 05-06 kpro
i got this about a month ago easy install and has worked great ever since!!!!
11/8/2008 by Nichiren
Great service and hassle free ordering
I originally tried to buy the same o2 sensor from some other site but they let me order without telling me that they were out of that part until the next month! So I canceled my order with them and got this part from ClubRsx and the whole process was seamless. The sensor works as it should: got rid of my CEL and it seems that I have better gas mileage now than even before the CEL came on. If you have a part you need and you find it here on ClubRsx, don't waste time and just get it!
10/23/2008 by Tony
Denso OE Replacement Primary O2 Sensor for RSX -S
Perfect Fit, easy to install. My gas millage is decent once again, no more strong gasoline odor when warming the engine in the mornings. Fast shipping and easy purchase from Club RSX
10/22/2008 by Wil
The O2 sensor took away my CEL, and now im getting better gas mileage again, it doesn't smell like sulfur, and on startup, i don't smell gasoline anymore. So it is worth it replacing it, and no procrastinating.
9/24/2008 by Arnoldo Silva
type s 03 pre cat o2 sensor
Well it was worth the 180.00 to purchase a non used o2 sensor. Easy, Direct, a little tug but that that's about it. And the offset socket and wrench to wich i purchased at a local autoparts store made it reallly simple. I am having better gas mileage, shifting and throttle response is great. And yes it was cheaper than everywhere else especially being by DENSO.
8/11/2008 by Jeremy
This was a perfect fit for my 02 RSX-S. Took only about 5 minutes to change (make sure you have an offset-style O2 sensor socket). Great replacement item for an engine with 100k+ miles on it. Engine is smoother, slightly more torque and (perhaps most importantly these days) gas mileage is back up to 30-32 mpg.
7/28/2008 by Hamburglar
What can I say, it works perfectly!