P0139 honda

P 0139 code. Purchased a nice used 2005 Accord 2 door, 2.4 4cyl with 77,000 miles, After we drove off the lot CEL came on. returned to the dealer they fixed it said it was vacuum leak. About 1 week later the CEL came on again, This time I stopped at Advanced auto first, They scanned it and it had a P0139 code, secondary heated o2 …

P0139 honda. Step by step instructions. Enjoy then comment below. Thank you.

5852 posts · Joined 2013. #7 · Jan 1, 2022. The code P0139 is a slow response on the secondary O2 sensor, a lot of times the heater is not working properly. It is not getting heated up enough to give a good signal. Double check the wiring and make sure the connector is clean and no corrosion.

2005 Honda Accord LX 2.4L. Issue + repair history: MIL lamp on with recurring P0139 code. Rear O2 sensor replaced at 139k miles with a Denso unit. Vehicle returned at 142k with the same code, and the sensor was replaced again with a different Denso part number due to emissions mismatch. Vehicle returned at 144k miles with the …2994 posts · Joined 2006. #2 · Jan 16, 2021 (Edited) Short answer is yes, foulers are causing the code. Under certain conditions during deceleration, the ECM will test the response time of the O2 sensor. If it does not respond fast enough, because it has been moved out of the exhaust stream the code will set. If you are not completely ...Feb 23, 2023 ... Causes of a Hyundai P0139 Code: O2 Sensor Circuit Slow Response (Bank 1 Sensor 2) ... How to Fix Hyundai P0139 ... 2005 Honda Accord Oxygen Sensor ...Jun 14, 2020 · To diagnose the P0139 2008 Honda Accord code, it typically requires 1.0 hour of labor. The specific diagnosis time and labor rates at auto repair shops can differ based on factors such as the location, make and model of the vehicle, and even the engine type. It is common for most auto repair shops to charge between $75 and $150 per hour.

Normal causes for the P0139 Code: There could be a leak in your vehicle’s fuel injection system, which can cause extra fuel to be left in the exhaust system . Faulty rear O2 sensor wiring. The wiring could simply be loose or worn. Bad catalytic converter.If the oxygen in the exhaust gas increases, the air-fuel ratio becomes Lean. The ECM interprets Lean when the HO2S voltage is below 0.45 V. If the oxygen in the exhaust gas decreases, the air-fuel ratio becomes Rich. The ECM interprets Rich when the HO2S voltage is above 0.45 V. P0139 Nissan Code - HO2S12 Slow Response.Step by step instructions. Enjoy then comment below. Thank you.P0139 code: o2 sensor circuit slow response (bank 1, sensor 2) Help hondacivicforumP0135 supercharged civic kraftwerks Fixing p0139 cel after downpipe installP0139 help. Honda accord sensor 2006 code catalytic converter got 2009 locatedHonda accord 2006 p0139 sensor code .HondaP0139 Honda DTC P0139 Make: Honda Code: P0139 Definition: Secondary HO2S (Sensor 2) Slow Response Description: With the engine running for at least 2 minutes, coolant temperature at a minimum of 156 F (69 C) and the engine speed a maximum of 4,000 rpm, the secondary HO2S output voltage is 0.05 V or more for at least 10 seconds.2005 honda civic 2.0 i vtec type r 3dr hatchback final premier edition Honda civic hybrid p1130 code p0141 2003 codes cel p1420 2005 honda sport civic si image. photo 12 of 14. p0139 help - HondaCivicForum.com. World car wallpapers: honda civic 2005 P0139 code Honda cca1 44e4 bf1e. Honda accord sensor 2006 code catalytic converter …Jun 9, 2020 ... 8:46. Go to channel · Honda Fit 2 geração com luz de injeção acesa , sonda lambda ou modulo de comando ??? SCOPECAR SERVICE•4.8K views.Troubleshooting a HONDA P0139 "O2 Sensor Circuit Slow Response (Bank 1, Sensor 2)." code as well as fixes.

P0139 – O2 Sensor Circuit Slow Response (Bank 1 Sensor 2) P0145 – O2 Sensor Circuit Slow Response (Bank 1 Sensor 3) What is the code P0133 Bank 1 sensor 1? When the P0133 code is set, it means that the O2 sensor isn’t altering the voltage output as it should when the air-fuel ratio changes. For that reason, it’s categorized as having a ...The engine code P1157 refers to the o2 sensor before the catalytic (paid $132) and P0141 refers to the o2 sensor on the catalytic converter (paid $121). Both of the sensors on my Element went out at the same time. I replaced the sensors myself (got both from a Honda dealer) and had a mechanic reset the Malfunction Indicator Lamp.Mar 10, 2019 · P0139 is a common OBDII code that occurs in many vehicles, including the Honda Insight. The code is triggered when there is an issue with the response time from the oxygen (O2) sensor when switching voltage levels. The Oxygen sensors are responsible for helping the ECM meter oxygen levels in the exhaust, and helping to. HNDAF: Get the latest Honda Motor stock price and detailed information including HNDAF news, historical charts and realtime prices. Indices Commodities Currencies StocksP0139 Honda: Code Meaning, Causes, Symptoms, & Tech Notes (With Video) The Heated Oxygen Sensor 2 (HO2S), after three way catalyst (manifold), monitors the oxygen level in the exhaust gas on each bank. For optimum catalyst. www.engine-codes.com That link has pictures and a video. Before spending the money, for sure look at the wire harness for ...HondaP0139 Honda DTC P0139 Make: Honda Code: P0139 Definition: Secondary HO2S (Sensor 2) Slow Response Description: With the engine running for at least 2 minutes, coolant temperature at a minimum of 156 F (69 C) and the engine speed a maximum of 4,000 rpm, the secondary HO2S output voltage is 0.05 V or more for at least 10 seconds.

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P0139 is your downstream O2 sensor, which is after/in your catalytic converter. Your car uses this sensor in part to help determine the effectiveness of the catalytic converter. If that sensor starts to fail, it can cause both of those codes. First fix the O2 sensor. Clear the codes and drive it for a couple days.Good morning, Quartz readers! Good morning, Quartz readers! France celebrates Bastille Day. This year’s military parade, which marks the 100th anniversary of America’s entry into W...A faulty bank 1 O2 sensor 2 and leaks in the exhaust system are some common causes of the P0139 code. Some common symptoms related to the P0139 code include an illuminated check engine light and a failed emissions test.Mar 10, 2019 · P0139 is a common OBDII code that occurs in many vehicles, including the Honda Insight. The code is triggered when there is an issue with the response time from the oxygen (O2) sensor when switching voltage levels. The Oxygen sensors are responsible for helping the ECM meter oxygen levels in the exhaust, and helping to.

P0139 is the OBD-II generic code indicating that the O2 sensor for bank 1 sensor 2 failed to have a voltage drop below .2 volts for 7 seconds during a deceleration fuel cut off. This failure shows that the engine control module (ECM) has determined the sensor response is too slow. What causes the P0139 code?I’ve since reflashed back to the tune I had before making the code disable change, and things are alright except I still have to original p0139 code for slow O2 response. 2017 SI with cobra PRL intake. TSP stage 1 race tune, clutch masters 450 stage 2 clutch, aluminum flywheel, ss clutch line, BOV.Aug 14, 2023 · The Secondary Heated Oxygen Sensor (Secondary HO2S (Sensor 2)) detects the oxygen content in the exhaust gas downstream of the three-way catalytic converter (TWC) during stoichiometric air/fuel ratio feedback control. DTC P0139: Secondary HO2S (Sensor 2) Slow Response (2005 model) Turn the ignition switch ON (II). Clear the DTC with the HDS. Start the engine. Hold the engine speed at 3,000 rpm without load (in Park or neutral) until the radiator fan comes on, then let it idle. Test-drive under these conditions:Jan 16, 2021 · 2994 posts · Joined 2006. #2 · Jan 16, 2021 (Edited) Short answer is yes, foulers are causing the code. Under certain conditions during deceleration, the ECM will test the response time of the O2 sensor. If it does not respond fast enough, because it has been moved out of the exhaust stream the code will set. If you are not completely ... Check wiring to the o2 sensor, check for voltage to the heater portion of the sensor, check for ground on the heater and lastly, check the resistance of the heater in the o2. Roy. SPONSORED LINKS. Was this. answer.Two minutes into the next drive the following day I smell un-burned fuel. I pull over and crawl all over the car. There were no leaks. The smell is from the exhaust, and clearly the engine is running rich. Shortly I get emissions notice and CEL, which turns out to be P0139 (Sensor Circuit Slow Response - Bank 1 Sensor 2). That's the down-stream ...I have a Honda Accord 05 LX Manual 5-Spd. 4cylinder 4-dr sedan. Also I'm getting codes p0420 and p0139. The Engine Light Came on 3 weeks ago for 2.5 days and then went off after I jacked up the car an … read moreDue to factors beyond the control of RB The Mechanic, it cannot guarantee against unauthorized modifications of this information. RB The Mechanic assumes no ...Troubleshooting a HONDA P0139 "O2 Sensor Circuit Slow Response (Bank 1, Sensor 2)." code as well as fixes.

When power is applied to the Secondary HO2S (Sensor 2) heater, if the Secondary HO2S (Sensor 2) output voltage is high or the SO2SG terminal voltage is high during feedback control, the PCM detects a malfunction and stores a Diagnostic Trouble Code (DTC). P0138 Honda Code - Secondary Heated Oxygen Sensor 2 Circuit High …

J. jacosajh Discussion starter. 4 posts · Joined 2012. #1 · May 17, 2012. I had the CEL come up on my 2006 Honda Accord. My OBDII showed P0139 (O2 Sensor Secondary). I took it to the local Honda Dealership and was told that they would clear the CEL. Then, if it came back on, I would have to get it re-serviced. Otherwise, I shouldn’t …I have a Honda Accord 05 LX Manual 5-Spd. 4cylinder 4-dr sedan. Also I'm getting codes p0420 and p0139. The Engine Light Came on 3 weeks ago for 2.5 days and then went off after I jacked up the car an … read more2005 p0139. Hi everyone! Last Thursday I was driving my 2005 I4 and I got a CEL and took it Advance Auto and I got P0139 - O2 sensor slow to respond. The light went off Sunday and just came on again today. After doing some research, it sounds like I should be replacing the secondary O2 sensor that involves the cat and passenger seat floor ...Dec 11, 2011 ... ... t know the answer. O2 Sensor Replacement for 2006 Honda Accord 4cy SE - P0139 & P0141 Codes. 250K views · 12 years ago ...more. Chris E. 1.71K.According to the specifications page on Honda, the Honda CRV has a towing capacity of 1500 pounds. For a fuel-efficient SUV, the towing capacity of the CRV is in range with its com...Definition of P0139. If your vehicle’s check engine light has come on and you’ve received a P0139 code, it means that the O2 sensor has detected a slow response from the downstream oxygen sensor located after the catalytic converter. This code is specific to bank 1 sensor 2, which is the sensor located on the driver’s side of the vehicle.Labor: 1.0. To diagnose the P0139 2009 Honda Accord code, it typically requires 1.0 hour of labor. The specific diagnosis time and labor rates at auto repair shops can differ based on factors such as the location, make and model of the vehicle, and even the engine type. It is common for most auto repair shops to charge between $75 and …It's State inspection time (due today) so I replaced both B1S2 and B2S2 O2 sensors, with non-foulers installed. I got P0139 and P0159 codes, indicating slow response from the new sensors. I removed the non-foulers, and got a P0420 code, which is what I got 5 years ago. I replaced the non-foulers on B1S2, and the P0139 returned (B2S2 appears to ...

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Honda has issued a service bulletin 13-055 to fix P3400 or P3497 and multiple misfire codes P0301 through P0304) on the vehicles listed below. P3400 and P3497 relate to rocker arm oil pressure switches B and C which measures oil pressure entering the variable cylinder management system (VCM). The VCM system disengages …Feb 8, 2023 ... ... Auto Repair•8.5K views · 8:33 · Go to channel · Error code P0139, O2 sensor replacement, Honda Accord - VOTD. Robert DIY•99K views ·...If the A/F sensor (sensor 1) voltage is low, the air/fuel ratio is lean, and the ECM uses A/F feedback control to issue a Rich command. If the A/F sensor (sensor 1) voltage is high, the air/fuel ratio is rich, and the ECM uses A/F feedback control to issue a Lean command. P1157 Honda Code - Air/Fuel Ratio Sensor 1 Range/Performance …o2 Sensor replacement: 45 to 60 minutes ($40 / $160 / $300)In this video I helped my sister replace the o2 sensor in her 2005 Honda Accord. It had the error ...P0139 is a common OBDII code that occurs in many vehicles, including the Honda Jazz.The code is triggered when there is an issue with the response time from the oxygen (O2) sensor when switching voltage levels. The Oxygen sensors are responsible for helping the ECM meter oxygen levels in the exhaust, and helping to to create the ideal …P0139 is a common OBDII code that occurs in many vehicles, including the Honda Insight. The code is triggered when there is an issue with the response time from the oxygen (O2) sensor when switching voltage levels. The Oxygen sensors are responsible for helping the ECM meter oxygen levels in the exhaust, and helping to.P0139 Symptoms. Check Engine Light will illuminate. In many cases, no abnormal symptoms may be noticed. In some cases, the vehicle will fail an Emissions Test. In some cases, the engine may "ping" and produce excess NOx.P0139 es un código OBDII común que aparece en muchos vehículos, incluido el Honda Civic.El código se activa cuando hay un problema con el tiempo de respuesta del sensor de oxígeno (O2) al cambiar los niveles de tensión. Los sensores de oxígeno son responsables de ayudar al ECM a medir los niveles de oxígeno en el escape, y a crear la mezcla ideal …Feb 8, 2016 · Troubleshooting. CEL Code P0420 This code occurs when the secondary O2 sensor is reading too much exhaust gases. The solution would be to remove the O2 sensor, loosen the lock nut and turn the defouler out 2 turns. Reset ECU. CEL Code P0139 This code occurs when the secondary O2 sensor is not reading enough exhaust gasses. Diagnostic fault code P0139 indicates that a vehicle’s bank 1/ sensor 2 oxygen sensor has failed to respond in a timely manner, during periods of reduced fueling or fueling cutoff. This code, as a general rule, relates to a vehicle’s bank 1, post-catalyst O2 sensor.Jay Safford. Automotive Mechanic. 16 years of experience. No, it is not the catalyst. The P0139 code is for the O2 sensor before the catalyst. The code is illuminated when the engine control module is testing the O2 sensor and it cuts the fuel to see if the O2 sensor detects a lean condition within 5 seconds. If it does not, then it sets the code.Install a new oxygen sensor: insert a new oxygen sensor into the exhaust pipe and tighten it with the wrench. Reconnect the wiring harness: connect the wiring harness back to the new oxygen sensor. Clear the code: use an obd-ii scanner to clear the p0139 code. ….

According to the specifications page on Honda, the Honda CRV has a towing capacity of 1500 pounds. For a fuel-efficient SUV, the towing capacity of the CRV is in range with its com...To diagnose the P0139 Toyota code, it typically requires 1.0 hour of labor. The specific diagnosis time and labor rates at auto repair shops can differ based on factors such as the location, make and model of the vehicle, and even the engine type. It is common for most auto repair shops to charge between $75 and $150 per hour.2005 honda civic 2.0 i vtec type r 3dr hatchback final premier edition Honda civic hybrid p1130 code p0141 2003 codes cel p1420 2005 honda sport civic si image. photo 12 of 14. p0139 help - HondaCivicForum.com. World car wallpapers: honda civic 2005 P0139 code Honda cca1 44e4 bf1e. Honda accord sensor 2006 code catalytic converter …Although they both use an “H” as their company logo, Honda and Hyundai are different companies based out of different countries. Honda is based out of Japan, whereas Hyundai is bas... Install a new oxygen sensor: insert a new oxygen sensor into the exhaust pipe and tighten it with the wrench. Reconnect the wiring harness: connect the wiring harness back to the new oxygen sensor. Clear the code: use an obd-ii scanner to clear the p0139 code. Mechanic for Honda: Nathanial. It should be under PCM and then functional tests or something to that effect. I think it comes up as RESET PCM. After PCM reset you hold the RPMs at 3000 until the cooling fans come on then let it idle for 5 minutes. Ask Your Own Honda Question.P 0139 code. Purchased a nice used 2005 Accord 2 door, 2.4 4cyl with 77,000 miles, After we drove off the lot CEL came on. returned to the dealer they fixed it said it was vacuum leak. About 1 week later the CEL came on again, This time I stopped at Advanced auto first, They scanned it and it had a P0139 code, secondary heated o2 …P0507 Honda Code Definition: Idle Control System RPM Higher Than Expected. Having a P0507 code indicates that the idle control system is running at excessively high speeds – this is also called a ‘high idle.’. A vehicle’s Engine Control Unit (ECU) must maintain a specific RPM range when it is idling – that is when it is not moving.Today we're going over the steps on how to locate, test and replace an oxygen sensor. Specifically, we're dealing with sensor 2, which is located after the c... P0139 honda, P0139 is a common OBDII code that occurs in many vehicles, including the Honda Stream.The code is triggered when there is an issue with the response time from the oxygen (O2) sensor when switching voltage levels. The Oxygen sensors are responsible for helping the ECM meter oxygen levels in the exhaust, and helping to to create the ideal …, Labor: 1.0. To diagnose the P0139 2009 Honda Accord code, it typically requires 1.0 hour of labor. The specific diagnosis time and labor rates at auto repair shops can differ based on factors such as the location, make and model of the vehicle, and even the engine type. It is common for most auto repair shops to charge between $75 and …, Nov 1, 2008 · I ran the codes and this is what I got. P0300 = cylinder misfire detected - Random Cylinders. P0301 = cylinder misfire detected - Cylinder #1. P0302 = cylinder misfire detected - Cylinder #2. P0303 = cylinder misfire detected - cylinder #3. P0304 = cylinder misfire detected - cylinder #4. P0139 = H02S 12 circuit condition (heated oxygen sensor ... , Mustangman May 30, 2018, 9:34pm 2. The P0139 code can mean a leaking fuel injector is allowing fuel to leak into the engine when you remove your foot from the throttle. It expects the O2 sensor to read a low value but it isn’t. It may also be caused by excess oil in the exhaust stream but you should know that from the look of the O2 sensor ..., Check wiring to the o2 sensor, check for voltage to the heater portion of the sensor, check for ground on the heater and lastly, check the resistance of the heater in the o2. Roy. SPONSORED LINKS. Was this. answer., Probable O2 Sensor. P0139 P0141 Codes Included. Hi All. My 07 Accord Sedan EX w 135k has a check engine light. Came on a few weeks ago and I’ve been ignoring it. Attached are the codes. Mechanic at Pep Boys (don’t laugh-it was no charge) pulled the codes for me., Dec 11, 2011 ... ... t know the answer. O2 Sensor Replacement for 2006 Honda Accord 4cy SE - P0139 & P0141 Codes. 250K views · 12 years ago ...more. Chris E. 1.71K., 360glitch said: P0139 is not a dangerous issue. Your O2 sensor is not seeing enough exhaust gas to make it happy. If you have an adjustable de-fouler you can move the sensor more into the exhaust stream. If this is not possible, check for a P00139 disable within Hondata. I know I have seen it in other tuning software., o2 Sensor replacement: 45 to 60 minutes ($40 / $160 / $300)In this video I helped my sister replace the o2 sensor in her 2005 Honda Accord. It had the error ..., P0139 is a common OBDII code that occurs in many vehicles, including the Honda HR-V.The code is triggered when there is an issue with the response time from the oxygen (O2) sensor when switching voltage levels. The Oxygen sensors are responsible for helping the ECM meter oxygen levels in the exhaust, and helping to to create the ideal …, The P0171 code in a Honda Accord can be caused by several factors, including: Air intake leaks. Faulty or dirty mass airflow sensor. Fuel pump or fuel filter issues. Faulty oxygen sensor. Clogged fuel injectors. Identifying the specific cause requires thorough troubleshooting and diagnostic procedures., =====Claim your FREE engine code eraser 👉 https://free.nonda.co 👈=====nonda Auto DIY Center is the biggest ..., RECORD_ID: 3476920. Bulletin Number: Label Misprint. Replacement Service Bulletin Number: N/A. NHTSA Item Number: 10211560. Date Posted: 02-26-2016. Component Name: 350000 EQUIPMENT. Make: HONDA. Model: ACCORD. Year: 2014. Date Added: 05-09-2022. Summary: Today, February 26, 2016, American Honda Motor …, (RTTNews) - Honda, the world's largest motorcycle manufacturer, has announced its plans to launch electric motorcycles. Honda announced it would ... (RTTNews) - Honda, the world's..., The Honda Accord tops the list of most popular cars year after year. It’s not a luxury or sports car, so it might come as a surprise that the Honda Accord is also the most stolen c..., Aug 24, 2021 · The P0139 code stands for “O2 Sensor Circuit Slow Response (Bank 1, Sensor 2)”, which means there’s an issue with the signal from the rear oxygen (O2) sensor on bank 1. A faulty bank 1 O2 sensor 2 and leaks in the exhaust system are some common causes of the P0139 code. , Feb 23, 2021 ... ... P0139 engine code and its risk level. Engine Code P0139: O2 Sensor ... Causes and Fixes Honda P0171: Bank 1 System Too Lean. HVAC Mechanic ..., Probable O2 Sensor. P0139 P0141 Codes Included. Hi All. My 07 Accord Sedan EX w 135k has a check engine light. Came on a few weeks ago and I’ve been ignoring it. Attached are the codes. Mechanic at Pep Boys (don’t laugh-it was no charge) pulled the codes for me., On certain Ford vehicles, code P0133 indicates a contaminated HO2S sensor, exhaust leaks, shorted or open wiring, and improper fueling among other issues. Common causes of the P0133 code include a faulty oxygen sensor or air-fuel ratio sensor, a malfunctioning heater circuit on the oxygen sensor or air-fuel ratio sensor, and circuit …, HMC: Get the latest Honda Motor stock price and detailed information including HMC news, historical charts and realtime prices. Indices Commodities Currencies Stocks, Mechanic for Honda: Nathanial. It should be under PCM and then functional tests or something to that effect. I think it comes up as RESET PCM. After PCM reset you hold the RPMs at 3000 until the cooling fans come on then let it idle for 5 minutes. Ask Your Own Honda Question., Dec 1, 2018 ... Step by step instructions. Enjoy then comment below. Thank you., The 2 fuel trims are additive, if your LFT is +10% and your SFT is +5% your total fuel trim is +15%. The ECM learns and adjusts those values based mostly on the primary air fuel sensor. Well, P0139 has come back yesterday and remained on today. P0139 code came on/went off about 8 weeks ago., I started getting the malfunction light on in my Honda 2005 Accord and I took it to my friend's mechanic shop to get the diagnosis code and we found that it is P0139. - Secondary Heated Oxygen Sensor (Secondary HO2S) Slow Response. I am planning to take it to the dealer. I am surprised that it this came up on my car which has only 40000 miles ..., I ran the codes and this is what I got. P0300 = cylinder misfire detected - Random Cylinders. P0301 = cylinder misfire detected - Cylinder #1. P0302 = cylinder misfire detected - Cylinder #2. P0303 = cylinder misfire detected - cylinder #3. P0304 = cylinder misfire detected - cylinder #4. P0139 = H02S 12 circuit condition (heated oxygen sensor ..., Hondas are popular vehicles, and choosing one for your next purchase is a smart move. You can find used Hondas for sale in your local area, either from a dealership or for sale by ..., About Press Copyright Contact us Creators Advertise Developers Terms Privacy Policy & Safety How YouTube works Test new features NFL Sunday Ticket Press Copyright ..., Diag and replacement of 02 sensor (Bank 1, Sensor 2). Quick and easy work.Questions or comments, drop them below.Like, Share, Subscribe.Disclaimer:Due to fac..., This is a 2005 Honda and it is the same process for whatev... In this video, I will walk you through the steps to replacing an oxygen sensor in a Honda Element. This is a 2005 Honda and it is the ..., How to Fix HONDA P0139 Engine Code in 3 Minutes [2 DIY Methods / Only $8.24] - YouTube. nonda. 85.3K subscribers. Subscribed. 119. 21K views 2 years ago …, Here are the most common issues that cause the P0139 code in the Honda Accord. They are presented in order (somewhat) of most to least likely to cause the problem. Bad Oxygen Sensor – The O2 sensor …, P0139 Code. hey guys, i'm throwing a CEL and the code on my scangauge II is saying p0139, i have a test pipe with the DIY "defouler" u can make from the spark plug nonfoulers from the parts store. is this the same code everyone else gets from not having a cat or is mine different and should i start investigating the problem. i search on google ..., P0139 HONDA OBD Code Description. The Heated Oxygen Sensor 2 (HO2S), after three way catalyst (manifold), monitors the oxygen level in the exhaust gas on each bank. For optimum catalyst operation, the air fuel mixture (air-fuel ratio) must be maintained near the ideal stoichiometric ratio. The HO2S output voltage changes suddenly in the ...