Air Fuel Sensor - Direct Fit
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Denso Air Fuel Sensor - Direct Fit

Part No. 234-9021 Warranty Details  

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Denso is the OE manufacturer.
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Connector Gender:Male
Connector Type:Direct fit
Exact Fit:Yes
Heated:Yes
Length (Sealing Surface To End Of Connector):13.78 in
Thread Size:M18 mm
Wire Quantity:4

REVIEW SNAPSHOT®

by PowerReviews
DensoAir Fuel Sensor - Direct Fit
 
4.9

(based on 9 reviews)

Ratings Distribution

  • 5 Stars

     

    (8)

  • 4 Stars

     

    (1)

  • 3 Stars

     

    (0)

  • 2 Stars

     

    (0)

  • 1 Stars

     

    (0)

100%

of respondents would recommend this to a friend.

Pros

  • Easy to use (4)

Cons

No Cons

Best Uses

No Best Uses
    • Reviewer Profile:
    • Casual driver (3)
    • Was this a gift?:
    • No (8)

Reviewed by 9 customers

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Displaying reviews 1-9

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5.0

Very goof buy of excellent product!

By 

from fort smith, ar.

About Me Casual Driver

Verified Buyer
Level 1

Pros

  • Easy To Use
  • Original equipment

Cons

  • Absolutely No Problems

Best Uses

  • Large Cars

Comments about Denso Air Fuel Sensor - Direct Fit:

Original equipment, fit perfect, excellent buy.

  • Was this a gift?:
  • No

Comment on this review(earn points)

 
5.0

Fit great and took care of P1135 code

By 

from Ashburn, VA

About Me DIY'er

Verified Buyer
Level 1

Pros

  • Perfect Fit
  • Same as OEM

Cons

    Best Uses

    • 2002 Toyota Sienna

    Comments about Denso Air Fuel Sensor - Direct Fit:

    While the part fit great and took care of the issue, the installation was a bit difficult on my 2002 Sienna due to the location of the sensor. Could only do this with left arm/hand. Unplugging connector was hardest part, but use penetrating oil for a few hours prior to doing this to make removal easier. This fixed P1135 error code (Bank 1, Sensor 1) for me.

    • Was this a gift?:
    • No

    Comment on this review(earn points)

    (5 of 11 customers found this review helpful)

     
    5.0

    great product

    By 

    from Franklin, TN

    Verified Buyer
    Helpful Reviewer

    Pros

      Cons

        Best Uses

          Comments about Denso Air Fuel Sensor - Direct Fit:

          Fit perfectly. Check engine light and all codes are off. I only use Denso 02 sensors

          • Was this a gift?:
          • No

          Comment on this review(earn points)

          (5 of 10 customers found this review helpful)

           
          5.0

          Easy Peasy

          By 

          from Maryland

          About Me Casual Driver

          Verified Buyer
          Helpful Reviewer

          Pros

          • Durable
          • Easy to replace
          • Easy To Use
          • Exact Replacement

          Cons

            Best Uses

              Comments about Denso Air Fuel Sensor - Direct Fit:

              Simple to install. Saved over $200.00 by doing it myself.

              • Was this a gift?:
              • No

              Comment on this review(earn points)

              (5 of 12 customers found this review helpful)

               
              5.0

              Denso Air Fuel Sensors are GREAT!

              By 

              from Elizabethtown, Pa

              Verified Buyer
              Helpful Reviewer

              Pros

              • Easy To Use
              • It came with Anti-Seze

              Cons

                Best Uses

                  Comments about Denso Air Fuel Sensor - Direct Fit:

                  I pulled up on Car Ramps, loosened the sensor while "HOT". After it cooled I replaced it. I saved a lot of money and it works great.

                  • Was this a gift?:
                  • No

                  Comment on this review(earn points)

                  (7 of 13 customers found this review helpful)

                   
                  5.0

                  As Advertised!

                  By 

                  from Richmond, VA

                  About Me DIY by necessity

                  Ask me a question

                  Verified Buyer
                  3 or more reviews submitted

                  Pros

                  • Direct Fit

                  Cons

                    Best Uses

                    • For exact model

                    Comments about Denso Air Fuel Sensor - Direct Fit:

                    If you can get the old one out without tearing things up you can replace it with this one. Plan ahead by looking the job over; research how to undo the electrical connector so you don't break it (these are generally plastic and you probably have at least 75,000, probably over 100,000 miles on the vehicle by now and the connectors can get brittle with this amount of age). Look at the new part to see how the connector goes together to get an idea how to get the old one apart. Apply some parts loosener liberally on the threaded connection joint of the body but do not soak surrounding items; and let soak overnight if possible. Try to use a proper wrench if available and twist out counterclockwise. An open ended wrench will work but care must be taken with the fit and angle of use so as not to round the corners between the flats of the sensor body. An extended length handle or "come-a-long" will probably aid in the removal. Install the new one using the anti-sieze paste (that comes with the new sensor) on the threads. Take care not to get paste on sensor probe when re-installing.
                    Note: the rear sensor between engine and firewall can try your patience and requires a careful approach as there are some sharp edges on the way down there and part of the removal of this sensor is done by "feel".

                    • Was this a gift?:
                    • Yes

                    Comment on this review(earn points)

                    (7 of 12 customers found this review helpful)

                     
                    4.0

                    part arrived o.k. and works fine.

                    By 

                    from Oakland, Maryland

                    About Me Casual Driver

                    Ask me a question

                    Verified Buyer
                    Helpful Reviewer

                    Pros

                    • Durable
                    • Easy To Use

                    Cons

                    • Insulation wasn't as orig

                    Best Uses

                      Comments about Denso Air Fuel Sensor - Direct Fit:

                      The insulation on the new part isn't as heavy duty as the original. This doesn't affect functionality, however it might affect how long it lasts.

                      • Was this a gift?:
                      • No

                      Comment on this review(earn points)

                      (6 of 11 customers found this review helpful)

                       
                      5.0

                      Perfect original replacement part!

                      Pros

                        Cons

                          Best Uses

                            Comments about Denso Air Fuel Sensor - Direct Fit:

                            The part matched the original part number and was $100.00 less than the dealer.....came with anti-seize.

                            Buy some PB Blaster to loosen old part and use a sensor socket for removal. The sensor was right up front by the radiator.

                            Thank you Advanced Auto Parts !!!

                            • Was this a gift?:
                            • No

                            Comment on this review(earn points)

                            (5 of 10 customers found this review helpful)

                             
                            5.0

                            way to go!

                            By 

                            from Bel Air, MD

                            About Me Auto Enthusiast

                            Ask me a question

                            Verified Buyer
                            Level 3

                            Pros

                            • High-Performance

                            Cons

                              Best Uses

                                Comments about Denso Air Fuel Sensor - Direct Fit:

                                Exact fit!

                                • Was this a gift?:
                                • No

                                Comment on this review(earn points)

                                Displaying reviews 1-9

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                                Do you have questions about this product?(earn points for answers!)

                                 

                                Ask a question, get answers from real customers and in-house experts. Or contact Customer Care by email or call 1-877-238-2623.

                                13 Questions | 13 Answers
                                Displaying questions 1-10Previous | Next »
                                • Q:

                                  ON 2002 AVALON WHAT IS THE DIFFERENCE BETWEEN AN UPSTREAM AND DOWNSTREAM AIR FUEL RATIO SENSOR? I WAS TOLD THE FAULTY SENSOR WAS BANK 2 SENSOR 1.
                                  Asked on 7/22/2015 by HARV

                                  1 answer

                                  • CUSTOMER CARE

                                    A:

                                    Hi Harv, I'm glad to assist you! This application has three air fuel ratio sensors, two upstream and one downstream sensor. The upstream sensor (#234-9021) is referred to the Bank 2 Sensor 1 and Bank 1 Sensor 1. Those are located at the front and the rear of the engine exhaust manifold respectively. The downstream sensor (#234-4061) is referred to the Bank 1 Sensor 2, it's located under car in the back of the catalytic converter. Since you didn't mention the specific error code, it's hard to assist you further. I would suggest that you take your vehicle to a certified mechanic for further diagnosis.

                                    Answered on 7/23/2015 by Solomon
                                • Q:

                                  Is this a heated sensor?
                                  Asked on 3/5/2015 by Del

                                  1 answer

                                  • CUSTOMER CARE

                                    A:

                                    Hi Del, I'm glad to assist you! This Denso Air Fuel Sensor - Direct Fit - Part No. 234-9021 is a narrow-band non-heated sensor.

                                    Answered on 3/5/2015 by Solomon
                                • Q:

                                  Have a 2002 Solara V6.
                                  Which wires are for the heater coil and what should the resistance be? Just want to test to see which sensor is bad before replacing.

                                  Guessing the two black wires.

                                  Thanks
                                  Asked on 12/6/2014 by Dave from Berwick Maine

                                  1 answer

                                  • CUSTOMER CARE

                                    A:

                                    Hi Dave, I'm happy to help! Yes, the two black wires are for the heater coil positive and negative. The standard resistance across the heater is in the range 1.80 to 3.40 ohms.

                                    Answered on 12/18/2014 by John the Car-Doc from AAP
                                • Q:

                                  The description indicates that two are required. (Bank 1 sensor 1 and Bank 2 sensor 1.) Only my Bank 2 sensor 1 is bad, can I replace that one and leave the other, or must I replace both sensors?
                                  Asked on 9/15/2014 by Steve

                                  1 answer

                                  • CUSTOMER CARE

                                    A:

                                    I'm happy to help, Steve! You do not have to replace both upstream or Sensor 1 oxygen sensors. The two required indication is to inform customers that of the number of that sensor are used on the vehicle. With oxygen sensors, you only need to replace the failed sensor.

                                    Answered on 9/19/2014 by Heath, ASE Parts Specialist from AAP
                                • Q:

                                  do this package include both b1s1 and b2s1 sensor?
                                  Asked on 9/8/2014 by Jos from omaha, NE

                                  1 answer

                                  • CUSTOMER CARE

                                    A:

                                    Hi Jos, glad to assist you! This sensor is sold individually.

                                    Answered on 9/9/2014 by Vincent from AAP
                                • Q:

                                  I got a P1155 Diagnostic Trouble Code, which indicates the Bank 2 sensor (the one on the exhaust manifold toward the front of the vehicle). This is on a 2002 Toyota Sienna. Is this the correct sensor?
                                  Asked on 3/31/2014 by Mike from Stephens City, VA

                                  1 answer

                                  • CUSTOMER CARE

                                    A:

                                    Hi Mike, glad to assist you! A P1155 error code in a Toyota Sienna indicates a faulty rear air/fuel (A/F) sensor. The A/F sensor is one of the types of oxygen sensors used by the electronic control module (ECM) to regulate the amount of oxygen to fuel rations received by the engine to manage performance. This Denso air/fuel sensor would be an ideal part for your Toyota Sienna and should clear the P1155 code.

                                    Answered on 4/2/2014 by Vincent from AAP
                                • Q:

                                  MY SIEENA 2001 HAS A CODE P1155. WILL O2 SENSOR DENSO 234-9021 CLEAR THIS CODE?
                                  Asked on 1/28/2014 by DOC from ROCKVILLE, MD

                                  1 answer

                                  • CUSTOMER CARE

                                    A:

                                    Hi DOC, glad to assist you! A P1155 error code in a Toyota Sienna indicates a faulty rear air/fuel (A/F) sensor. The A/F sensor is one of the types of oxygen sensors used by the electronic control module (ECM) to regulate the amount of oxygen to fuel rations received by the engine to manage performance. This Denso air/fuel sensor would be an ideal part for your Toyota Sienna and should clear the P1155 code.

                                    Answered on 1/29/2014 by Vincent from AAP
                                • Q:

                                  What is the length of the wire on this sensor? I want to make sure it will be long enough to reach the connector on the engine. This is the front upstream sensor for a 03 Toyota Avalon.The exisitng OEM Denso sensor wire and plug is approximately 10 inched long.
                                  Asked on 11/8/2013 by indupete from chesterton, In

                                  1 answer

                                  • CUSTOMER CARE

                                    A:

                                    Hi indupete, good question! The wire length of this Denso Air Fuel Sensor - Direct Fit - part# 234-9021 is 13.78 inches.

                                    Answered on 11/8/2013 by Vincent from AAP
                                • Q:

                                  I have a 99 toyota camry le v6, I have bought an upstream 02 sensor and it didn't fit so I was told the problem was that I need an AFR sensor. Will this upstream sensor fit my car?
                                  Asked on 5/5/2013 by Reggie from United States

                                  1 answer

                                  • CUSTOMER CARE

                                    A:

                                    Sorry, this Denso Air Fuel Sensor Direct Fit (Part No. 234-9021) is not compatible for your 1999 Toyota Camry 3.0L 2995CC V6 FI VIN: 1MZFE. For further assistance, please feel free to call us at 1-877-238-2623 or visit your nearest Advance Auto Parts store and one of our representatives would be more than happy to assist you.

                                    Answered on 5/5/2013 by Max from AAP
                                • Q:

                                  Is this F/A sensor the same as the O2 sensor?
                                  Asked on 11/5/2012 by Javier

                                  1 answer

                                  • CUSTOMER CARE

                                    A:

                                    With reference to this Denso Air Fuel Sensor Direct Fit - part# 234-9021, both oxygen sensor and air fuel sensor have a similar function, but they operate differently internally and cannot go in place of one another. The AFR (Air Fuel Ratio) Sensor can be explained as an "ON/OFF" signal while the O2 Sensor is an analog signal. They both work in a never ending cycle. For any further assistance, please visit your nearest Advance Auto store or call us directly at 1-877-ADVANCE (238-2623) and one of our representatives there would be more than happy to assist you.

                                    Answered on 11/5/2012 by Vincent from AAP
                                Displaying questions 1-10Previous | Next »

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