Closed loop open loop o2 sensor


closed loop open loop o2 sensor Hi, I have been playing with an e38 for highway economy. Engine Knock Sensor. I have replaced O2 sensors and have fixed the problem in the past but . Open loop is used when the O2 sensors are not warmed up, failed, or when an enrichment mode (such as power enrichment) is active. So I guess that open loop is like a failsafe . 2014 . 7:1 A/F ratio (assuming gasoline). 27 nov. The sensors take time to warm up so when they are the car is in open loop where it runs off of the MAF sensor for fueling or the VE tables depending on what year it is. 2017 . Jun 14, 2021 · The second they do, the engine enters Closed loop. Once warmed up, fuel is metered by an active feedback loop with the O2 sensor, known as closed-loop operation. In this mode the ECU fine-tunes the fuel mixture as you drive. My beater 2000 Corolla has neither the front or rear sensor connected but I can still 'trick' it into entering closed loop. That being the case you can easily return to the stock set up just to pass emissions. Anyone have any ideas? Needless to say I ordered a new O2 sensor. 4ish AFRs very smooth. Come to an idle and about 45 seconds later like a swtich it goes to open loop. Once the engine warms up to approximately 30 to 35° F, the PCM goes into closed loop Short Term Correction and utilizes feedback from the O2 Sensors. 5 sept. " using open loop as a base but using the o2 sensors as the primary modifier. 23 mars 2006 . Heated Exhaust Gas Oxygen Sensor. 12 mai 2012 . 1 déc. Ive been running SD open loop for a few days now while I await my new o2 sensors and im kinda liking it. Feb 10, 2021 · Closed loop operation simply means that the ECU is making air/fuel ratio corrections based on oxygen sensor information. uego). The ECU tries to adjust fuel so that the O2 sensor swings back and . BMW have been running all new model bikes with Closed Loop systems in Australia . OBD systems are either in open loop or closed loop depending on engine temperature and which sensors the computer is relying on for data The PCM injector pulsewidth calculation also uses the INT and BLM correction factors based on O2 sensor feedback when it is in closed loop. System 2 Open loop due to . Along with . In open loop mode, the engine doesn’t listen to nobody, it just runs off a set of instructions based on where the throttle is at, where the revs are, and so on. May 10, 2020 · A sensor closes the loop. In closed loop, the O2 sensor readings can cause a modification to the values in the table. 2020 . My post-cat o2 sensor comes back as open loop in MES but doesn't post error code . You wouldn't want your engine to just shut down in the event one of your O2 sensors fails . 12 déc. The problem is that the . The only advantage to closed loop is if your state begins emissions testing that requires the use of the O2 sensor. load the ECU ignores the O2 sensor reading and operates in open loop. $03 Fuel System 1 and 2 Status is System 1 Closed loop - using oxygen sensors as feedback for fuel control. Jan 21, 2020 · What is closed loop and open loop ECU? Defining Open Loop and Closed Loop o2 Open loop is when the ECU is not referring to the o2 sensor for feedback. Now I know this sounds complicated, but it isn't. 22 sept. 16 juin 2008 . Most cars today are in closed loop almost immediately. Nov 02, 2007 · In Open Loop, the PCM changes pulse width without feedback from the O2 Sensors. 9liter Dec 23, 2010 · 1,500 Posts. It is constantly monitoring the oxygen sensor to enter closed-loop. I found a thread where someone had something similar going on but it was a while back and there was no resolution. Open loop is . The sensor in question is a lambda sensor, also known as an oxygen sensor or air/fuel ratio mixture sensor. Open loop . In closed-loop, the ECM relies on input from the O 2 sensors and other sensors to calculate the air-fuel ratio. When switching to the open loop it might feel like the throttle is surging. Open Loop Delay vs. 7. May 23, 2011 · Forcing open loop it cruises perfectly at 14-14. Open loop and closed loop are terms used in computerized auto controls On Board Diagnostics (OBDI & OBDII) is a term used to describe computerized engine controls to reduce emissions. 4. some long term fuel trims (adjustments for altitude and such). With the system configured like this, any sort of oxygen sensor failure is going to lead to extremely poor running and possible engine damage. Nov 23, 2017 · auF0164 LTFT Enable should be all that is required to disable closed loop permanently. 2007 . The coolant sensor is above a specified temperature about 40oC/104oF. Someone correct me if Im wrong, but the upstream O2 is kind of critical for proper fuel system control. But the other pre-cat O2 sensor is an open, and reading live data. In open loop operation, which is normally when the engine is first started after a cold soak overnight or after sitting for several hours, the PCM ignores the oxygen sensors while they are warming up in the exhuast stream. The ECU won’t run in a closed feedback loop all the time, so ‘open loop’ is used to describe the operation of the ECU when the mixture is not being adjusted in this way (usually when the engine is cold or when running under high load). This allows engine stabilization to take place before the engine goes into closed loop. 2010 . When i go into open loop it holds around . The PCM uses inputs from the MAP, Coolant Temp Sensor and the Intake Air Temp sensor, to name a few, to calculate the fuel . One has to remember that if the oxygen sensor from the closed loop system is removed, it will operate like an open loop system, so to make it . open loop can be caused by various sensors going bad but it has a corresponding code when that happens. Open loop ignores the O2 sensor and uses the preset fuel maps plus. In closed-loop mode, the O2 sensors don't adjust the fuel maps. While tuning closed loop should be disabled, otherwise the ECU will adjust the air/fuel ratio resulting in an inconsistent air/fuel ratio. Although the ECU can calculate injection duration very accurately without using information from the oxygen sensor, closed loop control brings the air/fuel ratio within the extremely narrow operating parameters of the three-way catalyst (TWC). Nov 19, 2018 · When the ecm is running in open loop mode,o2 sensor voltage will remain at a fixed value. There are specific tables stored in the PROM programming that contain the instructions the ECM uses to determine how much fuel to give the engine in this operating mode. 7 févr. Closed loop means the ECM is using feedback from the engine sensors to maintain a specific fuel ratio. your O2 sensor needs to run above 600 degrees to function. While closed loop o2 can be used with a narrow band sensor, its accuracy is not fine enough to consistently rely on its reading. (This depends on temperature) 2. Fuel system status bank 2: Open loop; Closed loop not complete . This air fuel ratio is critical for proper operation of the catalytic converter and provides the best compromise between low emissions, good fuel economy and performance. High octane runs even richer in open loop and uses even more fuel & less hp. Is there much downside to running in open loop in a boat? The computer still adjusts for air temp and elevation right? I don't want o2 sensors . The ECM operates in two run modes, open-loop and closed-loop. Now when it runs in closed loop, the air fuel ratio is being read by the o2 sensor and sending a signal to the . Dec 16, 2008 · Closed loop uses the reading from the O2 sensor to constantly tweak. So closed loop AFR control is almost always active. Mar 09, 2005 · It's a feedback loop that loops back on itself. 7:1), which is most efficient. Mechanic's Assistant: Have you located all of the vehicle's oxygen sensors? Are the wires leading to and from each intact and in good shape? Yes they are. 1 juil. 11 mai 2009 . To the best of my knowledge, only the H6 motors have this second O2 sensor and second set of parameters. Everything was fine for a . – The O2 sensors were analyzed during closed loop operation. Open loop is used whenthe O2 sensors are not . DTC. One of my pre-cat 02 is in closed loop. Lambda sensor heating - short / open ; Lambda sensor - implausible signal . If you disconnect the O2 sensor the ecu will resort to a default map of basic values just to keep the motor running, ie it runs 'open loop'. The adaptation table contains offset to the fuel map table. Easy way to check if your O2 is bad: mash the throttle. The ECU gets a complete "loop" of data. The VCM fueling generally operates in one of three modes: 1) Open loop, 2) Open loop STFT or 3) Closed Loop. If the engine fails to go into closed loop when the O2 sensor reaches operating temperature, or drops out of closed loop because the O2 sensor’s signal is lost, the engine will run too rich causing an increase in fuel . Or set the delay time to 1000000000 (this is actually clock ticks and not seconds) Or set auF0162 to 1000000000 for all temperatures. 7:1 Closed Loop A/F ratio = 13. #4 · Dec 23, 2010. This will mean the O2 sensor is never "up to temp" and hence the O2 logic remains disabled. I have set the coolant temp to 200 in the closed loop table to try keep it in open . Running rich on a TBI system is usually one of, Too high fuel pressure (not common) bad o2 (common) bad Map sensor or vacuum to it(TBI carboned up in base)(common) bad temp sensor, or most common of all, a bad ground to the temp sensor. The dash gauge and the PCM use 2 different sensors. The O2 sensor acts like an open circuit and does not generate any voltage when it is below 360°C(600°F). 14 sept. There are two types of o2 sensors, narrow band, and wide band. Any vehicle that has a catalytic converter requires closed loop operation in order to maintain the stoichiometric air fuel ratio (AFR) of 14. curious if someone can tell me what exactly triggers the swap from open to closed loop. Sep 27, 2017 · The engine runs in "open loop" when first started, before the oxygen sensors come up to operating temperature. My basic understanding of closed loop means that the trucks computer is using the O2 sensors to regulate the fuel flow to the injectors and open . 7:1. Detailed information about mixture control can be found in article "Mixture adaptation". A few people have asked about the O2 sensors and wide open throttle operation. Im debating about disconnected my primary 02 sensor, and forcing my car to stay in a open loop mode, because my car pulls the hardest when . 11 déc. In . This system also uses a narrow-band oxygen sensor (O2 sensor) plumbed into each exhaust header. Dec 23, 2009 · It looks this target A/F ratio up in an open loop fuel table indexed by RPM and engine load. When the base map is correct, the engine should run just as good in open-loop as it does in closed-loop. 26 mars 2006 . 3. It uses the MAF and O2 sensors to . 2015 . because in open loop it doesnt rely on the o2 sensors for feed back to . Closed Loop O2 Sensor Temp: Closed loop will not be entered until the calculated O2 Sensor temperature is above this. Whether it's electrically heated oxygen sensors and catalysts or other tricks used, it . The ECU is designed for 87 octane. O2 sensors only read the amount of residual oxygen in the exhaust and calculate the air/fuel ratio based on that data. In closed loop, the ECM reacts to the O2 sensor feedback, adjusting the fuel using first on the INT's (short term fuel trims) and then raising or lowering the . in the open loop / closed loop scalars that can affect this. (I still have the ECM temp sensor disconnected to keep it from going into closed loop too fast for now. so here's the facts on the OPEN/CLOSED Loop operation of our . My guess is its the O2 sensor thing keeping it in open loop. The fuel system status started out in open loop . 11. The best thing to do is monitor the o2 sensor data to see what it is telling the PCM. 18 mars 2021 . the F/A ratio to keep it at stoichiometric (14. A new closed-loop control system for EGR rate has been developed. Mechanic's Assistant: What is the model/year of your Volvo? 2000 S80 2. EGR systems are currently applied mostly with an open-loop control . Dec 23, 2016 · Bank 1 stuck in open loop with a new upstream o2 sensor, swap sensor connectors and still stays in open loop. The O2 sensor is the main sensor used for . So something is a miss between open and closed loop. The VCM fueling generally operates in one of three modes: 1) Openloop, 2) Open loop STFT or 3) Closed Loop. Once the O2 sensors reach their operating temperature range, the condition is then know as "closed-loop," because now the engine computer knows . The open loop runs rich and kills your mileage. Sep 05, 2011 · Open loop simply means it does not use the feedback from the O2 sensors and when in closed loop it does, hints the name. RPM vs. Closed Loop = ECU recieves Signal - ECU processes data recieved - ECU . 2011 . Feb 02, 2020 · In closed-loop mode, the ECM gets feedback from the factory narrowband O2 sensors and senses whether the air/fuel ratio is lean or rich. 2013 . Oxygen sensors, knock sensors, intake air temp sensors ect to get real time . Sensors need to heat up before reading . So I recently installed K-pro on my 05 rsx-s and also installed a 02-04 o2 sensor, but the o2 sensor is bad and I'm waiting on my new o2 . This after the jeep is fully warmed up. closed loop operation in order to maintain the stoichiometric air fuel ratio (AFR) . I didn't even get one mile from home before it went to closed loop. Closed loop Long Term Adaptive Memory is maintained above 170° to 190° F unless the PCM senses wide open throttle . When cold, it uses "open loop" control as sensor readings would not be accurate until heated up. Mar 16, 2015 · MIESK5 NOTE; If da Engine Coolant Temperature Sensor (ECT) is Below 50 degrees F, then TAB is grounded &amp; sends air to atmosphere; If Between 50 and 190 Degrees F, Bypass Valve sends air to Diverter and to Manifold; If Over 190 Degrees F, it is in closed loop &amp; Air goes to Catalytic Converter; Bypass when at idle/Wide Open Throttle (WOT . The ECU will probably also lock out of closed loop if there . The O2 closed loop controller will measure the voltage of the oxygen sensor, determine whether the engine is running lean or rich, . DTC sets under the following conditions: Dec 11, 2015 · One has to remember that if the oxygen sensor from the closed loop system is removed, it will operate like an open loop system, so to make it work like a closed loop system; one has to make sure the O2 sensor is working properly and the ECU needs to be modified accordingly. 6:1 Open loop A/F ratio = 13. With a large enough change, such as cams or cubes, not only will the open loop tables be way off, closed-loop lock may not be achievable either. 19 déc. Ecu now ignores o2 readings and carefully measures air from the afm and refers to fuel maps for fueling. Right after a cold or hot start, a scan tool will report that the PCM is using open loop fuel control. if the o2's are sticking lean/rich it doesnt mean they are bad. For this reason I would suggest only using closed loop o2 with a wideband o2 sensor. The O2 sensor has varying voltage output, showing that it is hot enough to operate properly. 4:1 Variation = 1. DTC sets under the following conditions: Sep 21, 2017 · In Closed Loop (box checked), the WBO2 sensor feedback is entered into the equation, and the ECU will add/subtract fuel in an attempt to match the commanded AFR? If the above is correct, what would cause a car to run strong & smooth in Open Loop (box not checked), but not in Closed Loop? The sensor that would make sense is the upstream o2 sensors as most other are used during open loop as well but are run off a default program. 2012 . . . 27 mai 2013 . Where is your sensor located at? Do you have headers? It should be inches from the . If the oxygen content in the exhaust emissions is not correct the control unit responds and adjusts the mixture so that the oxygen content returns to the "Lambda window". FIXES FOR 02-CAUSED HEAT What we’ve seen is that the O2 sensor equipped Twin Cam and Sportster models run in two separate and distinct modes, closed-loop on the sensors at idle and cruise, and open-loop on their fuel tables or maps on acceleration and at top end. May 16, 2021 · Based on the continuous feedback of the O2 sensors (too rich - too lean) it will adjust the opening duration of the injectors (closed loop). Jul 13, 2006 · Most all of the scanners will show open/closed loop and sensor data. Closed loop is when the ECU . The stock ECU only references a "narrow band" O2 sensor that delivers 2. Is there anything else that can affect fuelling in closed loop like this apart from the lambda sensor ? Apr 06, 2019 · The system is ALWAYS in closed loop so long as the O2 sensor is warm and ready. An "open loop" operation is created by an open O2 sensor circuit or a cold O2 sensor. For now im just running without O2 input and its fine, if a little rich. My tuner said he can't get either of the front o2 sensor readings and that. Closed Loop is idle and cruise, that's it. Closed loop means the system is "closed" or looped feedback (maf,map, o2 sensor data etc) while the ecu is making adjustments. May 05, 2016 · open loop is determined by MAP, crank (speed), intake temp and coolant temp (cold curve?). On an engine with heated o2 sensors,closed loop begins once the engine reaches operating temp & the o2 sensors reach 625+°. o2 sensor heater core is bad, the o2 wiring has a short or some malfunction, or the o2 itself needs complete replacement. Even more strange I don’t have a cel. I run on a FI/c, the car was tuned on a ''acceptable'' level, by modifying the volts sent to the O2 while closed loop. My scan tool tells me my Renix ecu is staying in open loop. Jun 08, 2016 · What i meant was the in closed loop my trims are good and fueling is good swinging around stoich. 2009 . O2 sensor correction is not used in open loop. Closed loop is when the ECU does refer to the o2 sensor for feedback. 19 juin 2017 . In closed loop, the PCM uses the . In open-loop, the ECM relies on a set of rules located in PROM to make fuel delivery decisions. 11 juin 2012 . 14 avr. 6. General Tech - Oxygen Sensor/O2 system stays in closed loop?? - 03 6. Yes, unplug your O2 sensors and watch it do just that. Then check the short term fuel trims and see if that is telling us something different. If the exhaust is poor then the oxygen sensor alters the voltage maximum by 10mm volts. EKS. See full list on autotap. What about your Throttle Position sensor? What's it showing? TPS position has alot to do with Open/Closed loop. If you start an engine from cold without letting the O2 sensor warm up first, it takes roughly 15-20 seconds for the O2 sensor to come online after the engine starts. 0 Silverado, I have been watching some live data on my engine and sensors, . Open loop means it is using factory settings to give more gas on start up. Instead, they completely take control away from them, causing the temperature and pressure . When the car is in closed loop mode its use's various sensors Eg. In that case, the ECU locks itself in open loop mode. closed loop is where your car's AFR will run to a specified target AFR (o2 sensor feedback), which requires a wideband (ie. So does Engine Coolant Temperature for that . The sensor that would make sense is the upstream o2 sensors as most other are used during open loop as well but are run off a default program. ive herd its, time, o2 sensors, temp sensors, . 24 juin 2020 . Using the o2 sensor the ECU will modify its fuel table based on the readings the o2 sensor is seeing. 2006 . Over 50% throttle and 4k RPM is pen loop mode, where the ECU ignores the O2 sensor and . 9 févr. 94/95 lambda. higher reading= rich 450-900mv Jun 13, 2006 · In closed loop, the oxygen sensor works tells the ECU how much air is in the exhaust gas, so the ECU can work out if it got the mix right. Closed-loop fueling allows the ECU . 24 juil. Closed loop occurs when the O2 sensor is read out and used to adjust the fuel. So one of three things. The factory front O2 sensor switches abruptly around 14. The best way to do this is to set both the minimum and maximum short term trim adjustments to 0. 17 déc. 21 août 2014 . O2 sensors, Exhaust Gas sensors and probably a few other names as well. Note that there are 2 kinds of open loop. 1/ At large throttle openings or high speeds, both configurations (with or without O2 sensor) run open-loop and slightly rich. Based on this information, it adjusts the injector pulse width to maintain the correct air/fuel ratio at idle, cruise, or part throttle, even if your tune isn’t perfect or conditions change. Sep 29, 2016 · I always thought oxygen sensors were needed for closed loop operation. 6 janv. Open loop = >70-80% throttle. WOT is ALWAYS Open Loop and has nothing to do with cold vs. During open loop operation, the ECM ignores the O2 sensor input when making fuel delivery calculations and relies on the other sensors to determine fuel delivery to the engine. May 15, 2021 · This is an Odd one. Will not go from closed loop into open loop on diagnostic computer 19 janv. Stock O2 Sensor Kev’s O2 Controller Closed loop A/F ratio = 14. the pcm can only correct so much. The open loop is actually a bit more adjustable than the closed loop so if its running fine stick with it. 25 janv. This closed loop operation results in a constant flip-flop between rich and lean, which allows the catalytic converter to minimize emissions by keeping the overall average ratio of the fuel mixture in proper balance. I let the engine get to about 185 F or higher, turn the car off for a few seconds, then restart it. If your O2 sensor(s) are bad they will cause it to drop back into open loop too. 3 Variation = 0. Jul 05, 2021 · This is extreme over reliance on the ECUs closed-loop capabilities. Within a Closed-Loop Engine Control System. O2 sensor(s) is monitored by ECM. 5 volts of signal if the O2 level matches 14. 2 avr. The easiest explanation is closed loop = ECU uses oxygen sensor(s) to determine fuel/timing control. Jun 01, 2009 · If you do not have a O2 sensor on your engine, the engine is always running in open loop - the fall back default setting for timing and injectors. These two conditions account for the majority of the car's operating time. All my tuning had been focused around closed loop and wot. It basically means the fuel is being metered with MAP/MAF as the primary input. 13 mai 2004 . 4:1 Open loop A/F ratio = 13. Diagram 1 - Components & Sensors. This can also be felt at . The o2 sensor is properly heated up by the exhaust gases. Once it switches to closed loop mode,o2 sensor voltage will begin fluctuating constantly. Your closed-loop EFI vehicle has an oxygen sensor before the catalytic converter to keep the engine tuned for top . 2 In stock form, the closed-loop runs the A/F lean. ModoHero. The most important. The fuel system status started out in open loop, then went to closed loop and finally . Opppen Loop-Normal • Open loop fuel system statusOpen loop fuel system status, oxygen sensor is not being usedfdbkffld as feedback for fuel control • Ford Motor Company has dfi dth i l ttdefined the various loop status that are listed herethat are listed here Jun 06, 2011 · If he had exaust leaks causing the o2 to read lean it would only cause issues with closed loop driving not open loop since the ecu ignores the o2 anyways under open loop so I dont think that would be it. 8 juin 2019 . So my car isn't getting cool enough to switch back to open loop and nothing really has changed. when the engine is under no load apart from keeping itself running, and (b) during part-load conditions (which we usually term 'cruising speed') where the engine is keeping the car at a constant speed. So, a bike with a PCV+AT and its WBo2 sensors, has its ECU permanently working in a closed-loop mode? otherwise I can't see the benefit of the . The ECU only gets inputs from the O2 sensors in Closed Loop. it will start up in OPEN LOOP mode because the oxygen sensor has not gotten . 10 mai 2011 . In closed loop operation the ECU uses the oxygen sensor to tell if the fuel mixture is rich or lean. In 'Closed Loop', the PCM will calculate the air/fuel ratio (injector on-time) based on the various sensors but mainly the O2 sensor. hot. Typically I would . The ECU is not modifying its fuel map but instead it is populating another map called adaptation table. Closed-loop and open-loop. Jul 26, 2021 · There is a great deal of difference between a close-loop and open-loop EFI engine, with the closed-loop system being far more fuel and emissions efficient, and the reason our vehicles driven daily are of a closed-loop design. 5v for over 128 seconds while running in closed loop mode. The system will stay in ‘Open Loop’ until the following conditions are met: 1. I attached some info about this. We can then conclude from the open loop conditions above that O2 . With the heaters, an oxygen sensor can start reporting live . it could mean they are doing there job and seeing a lean/rich condition from something. 25 avr. But as soon as it goes closed loop it stumbles with the AFRs all over the show. If not, the ECU knows which way its wrong and can make adjustments. Open loop STFT is used "Closed loop" feedback verifies the A/F mixture. Status stays in closed loop running of the oxygen sensors. The very start of cold start, the loop is open. Open loop takes no input from the front O2 sensors. Oct 07, 2006 · When it takes 15 minutes to go closed that means the heater didnt do its job and it only went into closed loop because the exhaust finally got the sensor to warm to its 600 deg. com All engines that have an O2 sensor are able to operate in closed loop mode. Closed Loop Options Apr 02, 2010 · 'Closed Loop" is the normal operation mode of the PCM. To be fair though, I would suggest that any high performance engine be equipped with a wide-band o2 sensor, and that this should be considered a must have. 5 févr. To get faster oxygen sensor readings, car makers added heaters to the sensors. are there any negatives to running . 24 juin 2003 . 2G Open loop mode (any one true) Throttle position too high (varies by RPM) Airflow too low (units are tricky, but it's very low) Coolant temp < 51F; Coolant temp > 228F; The O2 sensor did not switch around 0. For vehicles without oxygen sensors closed loop should be disabled. 20 févr. A . closed loop is determined by "sufficient operating temperatures and a idle or cruise condition. Open loop is when the ECU is not referring to the o2 sensor for feedback. – Both upstream oxygen sensors need to be replaced. Jan 12, 2021 · The powertrain control module’s use of the input from the oxygen sensor to regulate the fuel mixture is known as a closed feedback control loop. An average ECU using a narrowband sensor will generally only use the lambda sensor's output during two specific conditions:- (a) during idle, ie. A specific amount of time has elapsed after starting the engine. 7:1 air to fuel ratio (AFR) also known as lambda value of 1. In closed loop mode, the ECU checks itself by “watching” the front O2 sensor feedback. 13 juil. 4 janv. The specific values for the above conditions vary with different engines and are stored in the mem-cal. Most all of the scanners will show open/closed loop and sensor data. ) So, I am ready to throw O2 sensors at . 26 déc. I am getting a O2 sensor voltage display, . All is well, then after about a Min, the engine enters Closed loop and B1S1, B1S2, and B2S1 are reporting fine, their voltage is jumping up and down, as the o2 sensor should as it reports. Diagram 2 . This is referred to as "open loop" operation because no input is used from the O2 sensor to regulate the fuel mixture. "Open loop" should be called "No loop" or "Out of the loop". operating temp. Titania and Zirconia Lambda Sensors and Oxygen Sensors supplies theory and free advice. The oxygen sensors monitor exhaust gases for . Set auF0163 to 4096 degrees. ArgosNoble: How long should it take for a car to switch to closed loop on a cold start?? Late model cars with heated oxygen sensors, . 2 juil. Closed loop is, by definition, less static, because it takes the open loop map and adjusts it for real time O2 sensor feedback. Running the system in 'Open Loop' will ignore the O2 sensors and you can use that to "bandaide" out a lean running condition. So you have air going into the engine, through the engine, and out the engine. etc. closed loop open loop o2 sensor