This contamination causes the sensor to lose its ability to produce voltage and send the right signal. I changed the MAF sensor as mentioned in a previous thread but it didn't seem to help. the rear o2 sensor makes sure that your cat is still doing it job of burning any on burn gas. To schedule an oxygen sensor testing, bring your car into your local Meineke Car Care Center where you can let the car care professionals handle the precise work of oxygen sensor testing. To be able to determine 100% (+ /- 5%) that the O2 sensor is performing properly is a hard task to accomplish. Learn what does P0135 Honda O2 Sensor Heater Circuit Malfunction Bank 1 Sensor 1 means, location and how to repair? Oxygen Sensors (O2S) or Heated Oxygen Sensors (HO2S) need to reach a minimum operating temperature of 750 degrees F to produce an accurate voltage signal. Although the fuel consumption problem might still be o2 sensors fault. You can tell if Bank 1 is responsive by stabbing t. When Mode 5 is not available Mode 6 should be used to view oxygen sensor test data. The sensor's voltage reading should also be fairly steady (not changing up or down), and average 0. 0 V (referred to as the lean to rich response time) should be about 300 milliseconds. Unfortunately it is on my rear O2 sensor. If i had the o2 sensor in the exhaust stream the normal way, i could just install a diode that has a voltage drop, that way it feeds different voltage than the primary, since it doesn't have a cat. Jot down in a notepad the lowest and highest voltage reading from the digital multimeter in any one-minute period. 81ish again. The l 1 reference voltage for the sensor is 450 mV the same as the thimble-type sensor. The two O2 Sensors mirror each other (sinusoidal trace from 0. Getting Technical - Air Fuel Ratio Sensors. For pre-catalytic converter oxygen sensors used for fuel control: Less oxygen than optimal in the exhaust results in a signal voltage over 450 mV. Many WBOS controllers out there do not address the exhaust gas temperature fluctuations, and simply apply a fixed electrical power to the heater unit. Verify that the sensor voltage fluctuates rapidly between 0. 7:1 there is absolutely no current flow and the resulting voltage signal put out by the circuit is 3. !!!! then if you look at the pins number 1 and 2 they changed of color. 9 volt at idle. If the voltage values being sent back to the computer are outside the normal excepted limits, the computer will throw the code. An oscilloscope with high-impedance 10:1 probe can also be used to monitor the Voltage fluctuation. O2 sensor on the Grom and piggyback tuners. 040, I did that a few months ago when I put new ones in. 2 V, I am guessing because it was leaning out the fuel/air mixture. It could mean your vehicle is running to rich. If i had the o2 sensor in the exhaust stream the normal way, i could just install a diode that has a voltage drop, that way it feeds different voltage than the primary, since it doesn't have a cat. The theory is that the converter should be capable of storing extra oxygen that comes in when the mixture is lean (low upstream HO²S voltage) and releasing it when the mixture is rich (high upstream HO²S voltage). You should hear the engine idle start to change. Cars that have a faulty oxygen sensor will commonly have a poor idle, jerk erratically at a steady throttle or emit a rotten egg odor from the exhaust pipe. 21 V and does not increase to more than 0. CODE 13 - Oxygen Sensor. The front o2 reads. The light stayed on, and I later found that the wiring harness to the O2 sensor was crushed, and all 4 wires were exposed, shorting to ground, and each other. G ATW Engine Oxygen Sensor Control Workshop Manual view, print and download online for free. Anyways, I vag it and one code comes up: B2 S1 o2 sensor intermittent Doing live graphs, i pick all 4 o2 to see what are they doing. Revving the engine decreases it to about 10 mV. The front sensor is showing voltage fluctuations from 0 to 1. The sensor output voltage does fluctuate on acceleration, but at idle it stays at 40mV. Have noticed some poor performance after changing pcv. Also, is higher voltage richer or leaner? Currently I am seeing about. The pre cat sensor is an A/F sensor so normal range fluctuates a few tenths around 3. with throttle steady 2000 rpm and engine fully warm the voltage should be in the range of 60-85mv steady reading with very few fluctuations. If this fluctuation rate gets sufficiently close to that of the rear O2 sensor, the converter efficiency code would trip, even if the converter was in fact properly functioining. If you see the full supply voltage of 4-5 volts (the reading you should get from the ECU when the connector is pulled off the temp sensor) then the temp sensor or its ground wire are faulty. 2V up until 0. This is done by measuring voltage, which is essentially electrical pressure, at the battery and at the system component being tested (such as the alternator or starter) while under a load. 65v and my exhaust smells like crap telling me it is rich. Oxygen sensor working voltage around 0. With your other hand, touch the battery ground. - When given full throttle and going rich, rear sensor tends to read 85%-95% voltage while front sensor reads 100% voltage. 45v at idle while the o2 sensor with the grey/light blue wire shows that it fluctuates between. I've found that under normal cruise conditions if O@ voltage hangs on one side of stoich and/or the other for a while that it's due to a bad or failing O2 sensor. The O2 sensor voltage readings are also flat lining in the log. Air Flow Sensor Testing DME Temperature Sensor Testing Throttle Position Switch Testing Speed and Reference Sensor Testing Oxygen Sensor Testing. Once suffient O2 sensor voltage fluctuation is observed by the PCM, closed loop is entered. I have a question regarding the operation of O2 sensor 1 (upstream) and O2 sensor 2 (downstream). O2 sensor not fluctuating Did some datalogging today. The sensor output voltage does fluctuate on acceleration, but at idle it stays at 40mV. No CEL at all or codes to read. The O2 sensor works like a half volt battery and it charges and discharges depending on the oxygen content. My millage has not been what I think it should be so I hooked a multimeter and a air/fuel mixture gauge up. Run the engine at 3000rpm for at least 30 seconds, then take a voltage reading from the sensor. Jun 30 If it fluctuates you may have a vacuum leak or a leaky fuel injector. What do these O2 sensor readings mean? I've been trying to get this thing to idle more comfortably and fixed some issues, but haven't made much progress. When an O2 sensor heater fails, it usually sets off the MIL or check engine light. Its still doing the lean/rich waveform, but its all internal to the sensor. The time taken for the voltage to change from 0. Rev the engine to approximately 2000 RPM. Trouble Code 13 indicates that the exhaust stream oxygen content sensor is not responding as expected. Question is I was watching the live data while my wife drove in the city and when under acceleration the voltage from the down stream O2 sensor would drop to. Typically, an O2 sensor creates a voltage due to a chemical reaction resulting from an off-balanced gasoline to oxygen ratio. Such controller considers the oxygen sensor ready for use only when as a result of the heating of the sensor, it can change the voltage in range greater than ±150mV ~ ±250mV. Is the front O2 sensor a wide band sensor on all RS's or just 2000 and newer?. 2L and I have scoped my O2 sensor at idle and see. It is only used for closed loop operation, to switch the mixture between rich/lean, letting the 3-way catalytic converter do its job. The oxygen sensor can last up to 100K miles, but typically you would experience problems sooner than that. You should hear the engine idle start to change. P2A00 code definition. The timing of the rough idle exactly coincided with Voltage on 02 Bank 2 Sensor 2 dropping to 0. A correctly configured Hyundai Elantra Oxygen Sensor continually tracks how much oxygen which is forced your vehicle's engine cylinders. The l 1 reference voltage for the sensor is 450 mV the same as the thimble-type sensor. 1 volts for a second or two. 000075, with essentially no fluctuation. I totally get that an O2 sensor should not put out more than 0. With a leaner mixture, the percentage of oxygen present in the exhaust is higher and the the O2 sensor voltage swings below the 450V threshold to a lower value. The time taken for the voltage to change from 0. I replaced an O2 sensor on my TJ in an attempt to fix a check engine light. KManager Configuration. If you get too high an exhaust temperature or your vehicle S performance drops,. If the fuel/air ratio is normal (not fluctuating) the reading at the postcat O2 sensor should be fairly constant. 706 Theres no fluctuation it stays at those two #s throughout the whole datalog. The theory is that the converter should be capable of storing extra oxygen that comes in when the mixture is lean (low upstream HO²S voltage) and releasing it when the mixture is rich (high upstream HO²S voltage). NOTE: Unlike the front O2 sensor (O2S11), whose voltage varies constantly/rapidly between. Turn the vehicle back on and check the reading on the voltmeter. As with any trouble code detected, you should not assume the presence of either one of these codes indicates the MAP sensor itself is bad. Diagnosing a plugged converter is fairly easy, but diagnosing converter efficiency requires tapping into the OBD II system with a scan tool to check for codes and to. Are you getting a P0430 code because Bank 2 catalyst isn't cleaning the exhaust. in order to protect them from fluctuating input voltage. Consequently very rough engine running very rich. When an oxygen sensor in a vehicle starts to have issues, either from a bad fuel mixture or the sensor itself going bad, it will trigger a number of codes in a vehicle computer. Also noticed car getting less mpg and not as quick. You can still however check the voltage to confirm the current air fuel ratio as well as force the sensor rich and lean to test it. Testing the O2 sensors 94-95 5. A fault code for an O2 sensor will indicate the sensor location by sensor number (1, 2, 3 or 4) and by cylinder bank (1 or 2). The reading should fluctuate rapidly. You can verify it by probing it and seeing the voltage fluctuation. 2 different technicians checked it with me also watching the meter, and both confirmed that the sensor was not functioning 100%, but about 70%. How The O2 Sensor Works: The O2 sensor can be considered a small battery that has an operating range of 0 to 1 volt when fully warmed up to 600°F. 4L car (pick up, SUV) is not that hard to do. This kind of deterioration can be caused by a variety of substances that find their way into the exhaust such as lead, silicone, sulfur, oil ash and even some fuel additives. The oxygen-rich excess air can't burn completely and leaves the engine with the exhaust. Revving the engine decreases it to about 10 mV. The fluctuating values of the residual oxygen are sent to the engine control unit as a voltage signal. I'm surprised you have not got codes relating to a/f sensor (B1S1) and the rear o2 sensor ( B1S2) given the voltages you observed on those sensors. P013C-O2 SENSOR 2/2 SLOW RESPONSE - RICH TO LEAN. The best way to test an O2 sensor is with a digital oscilloscope. Integrator 2 fluctuates from approx. You are reading the voltage drop from between the reference and sensor cell, not actual sensor voltage. :) Try 5650 or 5648 Thanks so much. 2 volts to above 0. Standing facing the Flywheel end of the engine, Bank 1 is located on the right hand side of the engine, there are two sensors one upstream, on the engine side of the catalytic converter, and one down stream on the exhaust side of the catalytic converter. AUDI A3 1999 8L / 1. 29v With no O2 sensor connected !. If the signal tends to show high voltage with little fluctuation, excessive unburnt fuel is reaching the sensor. How to read oxygen sensors and short and long term fuel trims. Learning how to check an oxygen sensor (O2) will help you confirm a potential problem with the sensor in your vehicle before you spend time and money replacing a unit that might not even need a replacement in the first place. The oxygen sensor control for oxygen sensors behind the catalytic converter (B1-S2 and B2-S2) are without engine load at certain operating conditions not active, that means, the third place of oxygen sensor control for oxygen sensors behind the catalytic converter can fluctuate between 0 and 1. G ATW Engine Oxygen Sensor Control Workshop Manual online. When Monitored: With the engine running, vehicle speed above 96 kph (60 mph), throttle open for a minimum of 120 seconds, ECT greater than 70° C (158° F), catalytic converter temperature greater than 600° C (1112° F), and downstream oxygen sensor in a rich state. The heated oxygen sensor 1 has a closed-end tube made of ceramic zirconia. 15 V or more but the A/F sensor voltage output is more than. 2v is constant across the tach, then yup, time to replace them sensors. The rear 02 sensor voltage seems a lot flatter on the graph with smaller fluctuations. Reply 1:. When I was graphing the front O2 sensor the voltage readings were steady around 18000. If any of these O2 sensors fails, ECU can no longer get correct signal outputs for the proper air to fuel ratio, which can result in poor engine performance and decreased gas mileage. 01 / Piece, United Kingdom, SST, LOX-02. The air-fuel sensor can be tested just like an oxygen sensor by forcing a lean and rich condition, making sure the sensor quickly and accurately responds. I was recently able to catch it with my scanner and it was P0135 (B1S1 heating circuit malfunction). If after you do this there is not any fluctuation in the voltage then that is a good indication that the o2 sensor is bad. The rear heated oxygen sensor (HO2S) normally sees a fluctuating voltage between 0 & 1 volt, for this DTC you'll likely see the voltage "stuck" at 0V. Ok so just put in a brand new mass air flow sensor and it still coding out po102 which is low mass air flow current. This is neither rich nor lean. 90625 % 19:35. The Jeep's ECU sends out a constant ~5 volts to most of the sensors (including the 02) and then interprets a condition based on the amount of voltage it recieves back on a third wire. 1 to 1 volt fairly rapidly when it is working properly. It cannot be used to monitor AFR at all. 30V from pins 1-2 with the engine hot and running and the sensor connected. As the catalytic converter warms up, the downstream oxygen sensor (bottom) changes from a switching to a constant-voltage signal. Denso Oxygen Sensor is designed to detect the amount of oxygen in the exhaust stream. Toyota service replaced TURBO PRESSURE SENSOR DENSO 079800-5130 TOYOTA 89421-20210 Fault P1250 on Rav4 D4D 116 HP Rav 4 World is the internet's largest Toyota. What is the function of the three wires leading to the MAP sensor? One of the wires provides a precise 5 volt power supply from the PCM. The O2 sensor shown in picture is not what I am currently using. Once suffient O2 sensor voltage fluctuation is observed by the PCM, closed loop is entered. I "think" it may be an issue with the catalytic converter so I got a scan tool and read the live data for the 2nd O2 sensor. The sensor's voltage reading should also be fairly steady (not changing up or down), and average 0. It ran smoother, but the O2 sensor is definately out of spec and not fluctuating like it should. The voltage should fluctuate. The O2 sensor can be considered a small battery that has an operating range of 0 to 1 volt when fully warmed up to 600°F. If you suspect it is, install a sensor bung at a better location, use a taller O2 sensor bung or use an Innovate Motorsports HBX-1 to move the sensor probe out of the direct exhaust stream. While we watch our upstream O2 sensor switch from high to low and back again (200 - 750 - 200) our downstream sensor should follow it but in a very reduced fashion. Efie new instructions and schematic plans. !!!! then if you look at the pins number 1 and 2 they changed of color. The sensor 2 (after cat) is a short range sensor which detects oxygen content in the exhaust by feeding a rapid fluctuating voltage back to the ECM. In the voltage graph above, the engine is warming up and the upstream oxygen sensor (top) begins sending a switching voltage signal to the PCM. Obviously, replacing the sensor was not the proper fix. The time taken for the voltage to change from 0. The internal circuitry used in a wideband oxygen sensor produces a digital pulse width modulated signal that makes it quite different from a conventional oxygen sensor that produces an analog signal ranging from 0. 30V from pins 1-2 with the engine hot and running and the sensor connected. To check if the O2 sensor is functioning: disconnect it and find which terminal is the signal wire and the hook positive test lead to that and then ground the black lead to see if the signal fluctuates. I havent had time to mess with it but Ill report my findings tomorrow. The time taken for the voltage to change from 0. On early OBD II systems, the post-cat O2 sensor should show little or no voltage fluctuations on a scope waveform, since all the mixture fluctuations are being absorbed by the catalytic converter. com info@sensore-electronic. Even with the rear out of the exhaust it still reads crazy. The O2 sensor can be considered a small battery that has an operating range of 0 to 1 volt when fully warmed up to 600°F. The ECM then compares the readings of the two O2 sensors to determine if the converter is functioning within set parameters. Basically, I can't get a stable. Consequently very rough engine running very rich. The voltage off the computer was tested and it turned out that the voltage for the sensor was fluctuating which was causing the flag. Locate the oxygen sensor signal wire The easy way to do this is to look it up in your Haynes, Clymer or Chilton manual for your car. they are silver instead of copper !!!! compared to the pins of the front o2 sensor. Have noticed some poor performance after changing pcv. I have a 95 geo metro. You can then read the O2 sensor volts. I ran the block to check the voltage of both front and rear sensors. To be able to determine 100% (+ /- 5%) that the O2 sensor is performing properly is a hard task to accomplish. This sensor is the master switch in the fuel control feedback loop. I am trying to figure out what is wrong with the Catalytic Converter/O2 Sensor system on my e46. The voltage will drop a bit at idle and raise a little when running but should always be stable and not varying like the front sensor. At idle the oxygen sensor should be between. 65v and my exhaust smells like crap telling me it is rich. That’s why they’re also called “wideband” O2 sensors. A good sensor will oscillate from below 0. That would point out a defective or low oxygen storage functionality on the converter On early OBD II methods, the submit-cat O2 sensor ought to present little or no voltage fluctuations on a scope waveform, since all the mixture fluctuations are being absorbed by the catalytic converter. 2 volts to above 0. Check the leads and the plug to the AAC plus take a good look at your vacuum hoses. Or unplugging the front driver side O2 sensor and the Harness and grounding the black wire at the sensor and probe the red/black wire to see the ground. O2 sensor voltage not fluctuating (i. Calculated measurement of combustion efficiency CO2, CO (air-free) and excess air Easy access to sensors New B-Smart® technology for in-field pre-calibrated sensor replacement O2 and sensor life indicator …. I replaced an O2 sensor on my TJ in an attempt to fix a check engine light. The following parameters should be used in KManager:. Given that it only happens when transitioning into open loop, I'd suspect that one or more O2 sensors is bad, and that the MAP vacuum fluctuating is not the root cause, but rather the result of a bad O2 sensor disrupting smooth engine operation and producing erratic vacuum by way of the engine. Battery (B+) voltage at least 11. AUDI A3 1999 8L / 1. When an O2 sensor heater fails, it usually sets off the MIL or check engine light. +43 2243 450 0, Fax +43 2243 450 315 www. With the meter connected, hold the engine harness end of the O2 sensor with your fingers. Sensor 1 should be the one in the front. 2v is constant across the tach, then yup, time to replace them sensors. All ok at first, much smoother, but now that new O2 sensor has failed in the same way. 37 Pages, PDF Size 0. Each flashing-light code is covered by a couple OBD-2 codes, so they're a little more specific. All O2 sensors are vented to the atmosphere which contains Approximately 21% oxygen. From what I read in this forum the voltage on the output of the O2 sensor is supposed to be around 450 mV (fluctuating a bit). If after you do this there is not any fluctuation in the voltage then that is a good indication that the o2 sensor is bad. An air/fuel sensor can read a much wider and leaner range of fuel mixtures than a conventional O2 sensor. !!!! then if you look at the pins number 1 and 2 they changed of color. But the Upstream sensor suddenly only reads 0. Looking at live data it starts at about 0. 9 (10) ohm to be precise the lower readings are due to the 5% tolerance of. so, with no sensor connected, you have a small antenna that will show voltage via induction(i think). I have a 95 geo metro. P0135 HONDA Description. I replaced an O2 sensor on my TJ in an attempt to fix a check engine light. Jun 30 If it fluctuates you may have a vacuum leak or a leaky fuel injector. As these two graphs show, the post-cat barely crosses 0. While the engine runs, the O2 sensor heats up and begins to generate a voltage within a range of 0-1,275mV. 5V reference. i checked the voltage of the post cat oxygen sensor it was fluctuating between 0. I'm surprised you have not got codes relating to a/f sensor (B1S1) and the rear o2 sensor ( B1S2) given the voltages you observed on those sensors. by way of fact the engine runs the sensor voltage is monitored and the pc will advance or decreases the gas mixture consistently. 05 v Observation: The front and rear O2 voltage readings for both Bank 1 and Bank 2 are almost identical and acting the same. I'm using a 1 wire set up. 45 volts or higher. I hooked up the O2 sensor and I have a constant. Commercial voltage regulators normally operate on a range of voltages, for example 150–240 V or 90–280 V. G ATW Engine Oxygen Sensor Control Workshop Manual view, print and download online for free. The temp sensor wiring goes into the wiring harness and along the firewall before joining with the O2 sensor wiring and going through the firewall to the ECU behind the right side kick panel. Question is I was watching the live data while my wife drove in the city and when under acceleration the voltage from the down stream O2 sensor would drop to. 2 volts to above 0. 2v is constant across the tach, then yup, time to replace them sensors. !!!! then if you look at the pins number 1 and 2 they changed of color. the rear o2 sensor makes sure that your cat is still doing it job of burning any on burn gas. The ECU makes constant adjustments in fuel delivery according to the signal generated by the oxygen sensor in order to maintain the optimum air/fuel ratio. My son has a 2003 Saab 9-5. The internal heater is simply used to get the sensor's tip up to operating temperature more quickly. After driving around to get coo. If you can probe the open circuit voltage with the engine running while you have someone vary the throttle, you should see fluctuations around one volt into your high impedance Fluke meter. If the sensor voltage is stabilized at the middle of the specified range (approximately 0. If you use the multimeter, you’ll know whether or not the voltage coming to and from the oxygen sensor is within spec, this can help you determine if it’s your 500’s O2 sensor, or wiring harness that’s the issue. The only way that a converter efficiency code could be caused by a bad rear O2 sensor is if the sensor's voltage fluctuation somehow sped up relative to the front sensor. Also, the engine management system either went off-scale or got in a tangle, which caused it to lose track of what was really going on. The S-AFC instructions list the air flow signal pin in drawing N-4A for an R33 with RB25DET made before 96. The O2 sensor works like a half volt battery and it charges and discharges depending on the oxygen content. If after you do this there is not any fluctuation in the voltage then that is a good indication that the o2 sensor is bad. If your oxygen sensor has failed, the code checker will generate a diagnostic trouble code that specifically indicates your oxygen sensor is bad. A properly functioning oxygen sensor will show a rapidly fluctuating output voltage between approximately 0. 5V? The following image clarifies my question. Its still doing the lean/rich waveform, but its all internal to the sensor. I bought a new sensor. A P0420 is catalytic converter below efficiency, and does not necessarily mean the cat is bad. end of the voltage scale. On the bad Buick however, the upstream sensor never moves off 450mv even though I'm monitoring the proper change in voltage right at the PCM with my DMM and stays there even when I start the engine but the downstream O2 sensor fluctuates normally. On the other hand, that the Bank 1 sensor 2 is following the same voltage swing as upstream sensor is an indication that the cat efficiency is probably low. Each flashing-light code is covered by a couple OBD-2 codes, so they're a little more specific. Test for O2 sensors behind the catalytic converter: Graph the rear and the front O2 sensor output. I go alot more into detail about everything. on Alibaba. I've read way too many posts on this forum where someone drives into the dealer, replaces all the 02 sensors and the next week the same codes are coming up. The procedure is turn on a digital port for millisecond, read the associated analog port, then turn off the digital port. When an O2 sensor heater fails, it usually sets off the MIL or check engine light. If you also see rapid voltage fluctuations from the downstream sensor then that is evidence the cc has failed. A P0420 is catalytic converter below efficiency, and does not necessarily mean the cat is bad. An amplifier (68) receives an output signal from the oxygen sensor (20) and generates a buffered output signal. At idle the oxygen sensor should be between. P2A00 OBD-II Trouble Code: O2 Sensor Circuit Range/Performance Bank 1 Sensor 1 P2A00 means there is an abnormal voltage reading from the O2 sensor, possibly due to a defective sensor, malfunctioning circuit, or leak. 1 volts and you run that extra voltage to the signal wire for the sensor, thereby artificially adding a bit of rich signal to the O2 sensor and making the computer continually. 8 volts almost every sec. Phase synchronous detection is used to extract these harmonic signals from the sense winding and convert them into a DC voltage proportional to the external magnetic field. A coil winding inside the sensor picks up the magnetic fluctuations from the vibration damper or the flywheel (or both in some cases). What would cause the mass air flow sensor constantly put out low input 43 Answers. How The O2 Sensor Works: The O2 sensor can be considered a small battery that has an operating range of 0 to 1 volt when fully warmed up to 600°F. We had a regular customer stop by the house with a check engine light on. Mercedes oxygen sensor simulator will allow you to drive without cat and still keep the CEL off. From what I've learned is that the 2nd O2 sensor (after the catalytic converter) should remain a constant voltage of around. The ECM's responsibility is to keep the oxygen sensor voltage switching between high and low voltage for optimum fuel efficiency, lowest emissions and highest miles per gallon. Magnum EZ CEL Fix Oxygen sensor simulator is available to all cars, trucks and SUV's fitted with 1 up to 4-wire narrowband zirconia exhaust o2 sensors working in the standard 0 up to 1. Car idles erratically and doesnt go pass. 7 Oxygen Sensor Voltage (Bank 2 Sensor 1) 0. This fluctuation is caused by interaction between the ECM/PCM and the HO 2 sensor, which follows a general pattern: detect, compare, compensate, detect, compare, compensate, etc. indice de codigos del sistema obd ll, mecanica automotriz. The only way that's possible is if the sensor has a dead short or your reading the wrong wires. O2 Sensor BX-SX Wide Range V (up to 8) - shows voltage for linear or wide-ratio oxygen sensors. Typically, O2 sensors just die and report a voltage of 0. P0135 HONDA Description. Driven about 70 kms since, not got the chk engine light. It does say that you can do a voltage test. 3D/74 - Oxygen sensor heater after catalyst, bank 2, open circuit BE/78 - Insufficient heat output, oxygen sensor after catalyst, bank 1, sensor heater faulty 98/B4 - Oxygen sensor voltage after catalyst, bank 1, open circuit I guess I have damaged them during the removal, or could something else be the issue? January 25, 2016. 0 Volt fluctuating voltage range. 0V (referred to as the lean to rich response time) should be about 300 milliseconds. While we watch our upstream O2 sensor switch from high to low and back again (200 - 750 - 200) our downstream sensor should follow it but in a very reduced fashion. The simplest setup is a single wire, which is the signal wire and the sensor get's it's ground from the exhaust pipe. 450 volts) and lack of it will send the voltage signal high (over 0. For the O2 sensor, touch a jumper wire from the O2 to the Vref terminal (*NOT* 12 volts or injector +12V) - check on TunerStudioMS for O2 sensor voltage. The voltage will drop a bit at idle and raise a little when running but should always be stable and not varying like the front sensor. As the engine runs the sensor voltage is monitored and the computer increases or decreases the fuel mixture constantly. 11 v; sensor 2, 0. Try testing the voltage with the O2 sensor unplugged, with the engine running and with the cat/exhaust hot. The downstream O2 sensor should show relatively constant voltage which indicates the cc is doing its job. What I see is that the commanded EGR went to 0% for about a minute, then three things happened simultaneously as the check engine light turned on: The voltage for 02 Bank 2 Sensor 2 went to 0 AND the rough idle started. 3v unless gets a overly rich input in which case it goes down to around 2. The LC-2 utilizes 100% digital wideband air/fuel ratio technology on the market!. While the engine runs, the O2 sensor heats up and begins to generate a voltage within a range of 0-1,275mV. 2) What you're looking for is the O2 voltage CHANGING. You should hear the engine idle start to change. So I wonder why the 2x1 sensor fluctuates as high as 1. 85v, normal working i disconnect the 2nd sensor. An air/fuel sensor can read a much wider and leaner range of fuel mixtures than a conventional O2 sensor. 7 ohms (which I believe to be a sufficient match). Hi all, I had my oxygen sensor replaced 6 months ago after codes 1221 and 1222 showed up. P0136 O2 SENSOR CIRCUIT P0141 O2 HEATER SENSOR CIRCUIT Can anyone tell me where to start with these. The oxygen sensor produces a small voltage signal that is interpreted by the electronic control unit (ECU) of the fuel injection system. The controller is coupled to the oxygen sensor and is configured to, for each of a plurality of stages of a regeneration process, determine a predetermined temperature for heating the oxygen sensor to, determine a predetermined internal resistance value of an electro-chemical measurement cell of the oxygen sensor associated with the. 79 steady (flat line) resistance reading: 192 steady (flat line) All (4) O2 sensors heater voltage: 2. 0 V (referred to as the lean to rich response time) should be about 300 milliseconds. An air/fuel sensor can read a much wider and leaner range of fuel mixtures than a conventional O2 sensor. The PCM uses the O2 sensor voltage to determine the air to fuel ratio. I get only about 30 mV on both the 260E and 300E. The voltage regulator compensates for the change in load. 843 and the o2s 21 goal volt shows 1. O2 sensor on the Grom and piggyback tuners. A few months ago, I was having my exhaust system worked on and the O2 sensors had to be removed to facilitate the work. It should be fixed for a short period at around 0. * rear 02 sensor wire voltage between pin 1 and 2: fluctuating between 10. It is only used for closed loop operation, to switch the mixture between rich/lean, letting the 3-way catalytic converter do its job. 2V up until 0. 8V swing on the o-scope but it swings only 1 cycle per second. Looking at live data it starts at about 0. The early style gauge was used on all models of 924s and on 944s up to the 1985 model year.