浅谈氧传感器引发的发动机怠速不稳故障及维修.doc

this type of operation for the safety technology. Without education and training in safety knowledge, shall not enter the construction site operations. To enter the construction site, you must wear a helmet, buckle chinstrap. Work at two meters high and must be fastened. When working at height, are not allowed to throw down or up the materials and tools and other objects. Persons not engaged in electrical and mechanical, prohibited the use of mechanical and electrical equipment. Building materials and components to be tidy and secure, shall not exceed the relevant provisions. Hazardous areas should be clearly marked, protective measures should be taken at night to set up a red light warning. In the operation, should adhere to their jobs, drunken operation is strictly prohibited. Special operations personnel (electricians, welders, boiler operators, blasters, lifting grid and pile drivers and commanding, shelf workers, machines, motor vehicle drivers, and so on) must be operating permits from the relevant sector professional training examinations, independent operation, operation focus, not to leave. Construction site prohibited to wear slippers, heels, skirt, sliding and studded shoes and barefoot, shirtless, and so on. Construction site of the scaffold (prohibition of the use of bamboo and wood materials setting), protective equipment, safety signs, warning signs, scaffolding wall may be supplemented, removed and need to be removed must be reinforced by the contractors agree. Construction site of the four (openings, stairs, lift head, hole) and the five-limb (balcony, framing, roofing, run (oblique) road and unloading platforms), protective measures and clearly marked. Are not allowed to sit at the feet of . Nails should be promptly removed. Drywall cut bricks are cut, no outside chopping. Preventing broken tiles fall hurt. Tools must always be mounted after good tool bag. In the Derrick (gantry) travel; in the Derrick (gantry) increased security measures are not taken to the following cleaning mortar, concrete and other debris; hanging baskets for a long time is not allowed to stop the air; after work basket must be placed in the ground, and cut off the power and lock box. Scaffolding on the Frost, snow, mud, and building waste time cleaning. Both ends of the scaffold to fasten to prevent probe Panel. Danger of overloading the scaffold: laying per square foot scaffold distributed load shall not exceed 270KN, piled up on the scaffold standard bricks of single side three storeys high. Wall removal of dangerous scaffolding; Sat down to rest on the guard rail danger; Set, dismantling scaffolding, Derrick (gantry) high, edges, vacant jobs, such as not wearing a seat belt at risk. Upper part of the ladder to fasten, antiskid measures are required in the lower part. Upper part of the ladder to hang, and lower banding. Ladder to fasten in the Middle, lower to have a non-slip steps, are not allowed to sit on it, riding moves. Altitude: personnel engaged in the Spider-man,stavebn tm vdce mst een. een by mlo zahrnovat analzu rizik, monost nehod charakteristik a nouzovch postup, nouzov zpracovn a obsah opaten. 4, integrovan pohotovostn plny, speciln havarijn plny a mst een by mly bt mezi sebou a s ostatnmi jednotky zapojeny v nouzi, kter jsou vzjemn propojeny. 5, havarijn pln by ml zahrnovat havarijn personl a organizace kontakt, nouzov rezervn seznam a dal informace. Informace by mly bt pravideln aktualizovny a zajist, e informace jsou pesn a platn. tyi, havarijn pln revize 1, Recenze pohotovostn plny pezkoumn formul a prvky pezkumu a opaten pijatch dvma zpsoby. Kdy host slou pedevm pro havarijn plny pro zznam v podob Recenze, prvek hodnocen pro nouzov hodnocen. . Kd pro porn ochranu konstrukce budov a nsk republice ny exploze nebezpen oblasti elektrick bezpenostnch pedpis a pedpis o porn ochranu design rafinaci ropy a chemickch podnik, napklad poadavky na pedpisech a nazench. 2. pi provdn instalace me zpsobit por, exploze, kter sti by mly bt pln nastaven peht, petlaku, micch pstroj, alarm (zvuk a svtla). 3. kde je holav plyn (pra) me unikat , holav plyn koncentrac detekce, alarm by mla bt nastavena. 4. vechny komunikoval s holav, vbun zazen s inertnm plynem, plynov penosov potrub, by mla bt nastavena zabrnit holavch a vbunch ltek do zazen, ale nemla bt samostatn zptn ventil. 5. holav plyn (pra) nastavit plamen svodi odvzduovac vvod, snadno pracovat, kde se zastavit ventily, aby pi vstupn vtrac potrub je v plamenech, peruil por plynu odvzduovac potrub ml bt nainstalovn v nejni hasicho zazen. 6. kdy dopravu holavch materil by mla odpovdat prmru potrub a stedn mrn odpor, sprvn zen prtoku, co nejvce se vyhnout statick elektiny. Antistatick opaten, jako jsou zazen, potrub, by mlo bt v souladu s technickmi pedpisy pro uzemnn design pro chemick podniky pslunch ustanoven. 7. nhl vbun petlaku nebo rychlho rozkladu vrobnch zazen nebo skladovacch zazen by mly bt vybaveny vbuchu (nevbun membrna), vvoz nonel trubice smrem k bezpenosti a aby prevence sekundrnch exploz, protiporn opaten. 8. vrobnthe principle of simplified EIA of construction projects in the region. In terms of land, linked to the implementation of urban and rural construction land increase and decrease, replacement indicators for priority areas project. Charges, into the projects of water, electricity, administrative charges and preferential policies. In the area of taxation, and settled in areas of industry and its production company, within 5 years after the completion of fiscal incentives to enterprises. In terms of financing, integration of land, tax, financial and other resources, and construct Government credit + business credit credit system, establishment of marketization, commercialization and modernization of the investment and financing platform; effective Bank-enterprise docking, encourages private capital into the Park, to raise industry development fund. 5, optimize the environment and service industries. To create policy lowlands, Highlands, integrity of service land, development land as the goal, to optimize the area under development environment. All administrative law enforcement departments to appoint a full-time personnel stationed in areas dedicated to coordinating and solving problems associated with businesses in this sector. When there are substantial issues, sector leaders arranged to personally intervene, in-person, in-person push tangible area building a green light, easy line. To further reduce and standardize administrative examination and approval items, simplify examination and approval links, improve efficiency; according to the .Since the educational practice of the mass line of the party, himself seriously in the education, practical control central eight rules and opposing the four winds and practicing three Suns, and check the spirit of Jiao Yulu, ideology, solicit opinions based on outstanding problems checked swing, careful analysis and reflection. Will now check report is as follows: first, adherence to the partys political discipline, eight in the central provision, change the style of the basic situation of 1, in compliance with the partys political disciplines. Conscientiously abide by the partys political discipline, abide by the Constitution and the rules and regulations of the party, in the political, ideological and maintain highly consistent with the CPC Central Committee on the action, there is no violation of the partys political discipline problems. 2, in the implementation of the central authorities of the eight provisions. Improving research, improving research methods, but there are less grass-roots units, primary first-hand an inadequate grasp of the problem, which is to be strengthened in the future. Second, construction, strictly in accordance with the provisions to streamline and improve the quality of meetings of the Conference. Third, streamlining file briefs, culture involves all aspects of propaganda and ideology, sometimes due to the practical needs of invention notifications, this area needs further浅谈氧传感器故障引起发动机怠速不稳故障诊断摘要：本文介绍了丰田佳美2.2轿车由于氧传感器故障造成的发动机怠速不稳故障 ，以及整个故障的分析诊断过程。关键词：废气再循环（EGR）阀、喷油量失准、氧化锆式氧传感器一、故障描述一辆丰田佳美2.2轿车，该车多年来一直运行状况良好，近期突然怠速不稳，发动机转速时高时低，加大油门时，能明显感觉到有些好转。试车证明，与用户反映的现象一致。因此故障现象描述为：发动机怠速不稳，转速时高时低变化。二、故障分析引起发动机怠速不稳的原因有很多，也有其特定的特点，下面就可能引起发动机怠速不稳的原因进行分析。 1. 进气系统 (1)进气歧管或各种阀泄漏 当不该进入的空气、汽油蒸汽、燃烧废气进入到进气歧管，造成混合气过浓或过稀，使发动机燃烧不正常。当漏气位置只影响个别汽缸时，发动机会出现较剧烈的抖动，对冷车怠速影响更大。常见原因有：进气总管卡子松动或胶管破裂；进气歧管衬垫漏气；进气歧管破损或其它机件将进气歧管磨出孔洞；喷油器O型密封圈漏气；真空管插头脱落、破裂；曲轴箱强制通风（PCV）阀开度大；活性炭罐阀常开；废气再循环（EGR）阀关闭不严等。 (2)节气门和进气道积垢过多 节气门和周围进气道的积炭、污垢过多，空气通道截面积发生变化，使得控制单元无法精确控制怠速进气量，造成混合气过浓或过稀，使燃烧不正常。常见原因有：节气门有油污或积炭；节气门周围的进气道有油污、积炭；怠速步进电机、占空比电磁阀、旋转电磁阀有油污、积炭。 (3)怠速空气执行元件故障 怠速空气执行元件故障导致怠速空气控制不准确。常见原因有：节气门电机损坏或发卡；怠速步进电机、占空比电磁阀、旋转电磁阀损坏或发卡。 (4)进气量失准 控制单元接收错误信号而发出错误的指令，引起发动机怠速进气量控制失准，使发动机燃烧不正常，属于怠速不稳的间接原因。常见原因有：空气流量计或其线路故障；进气压力传感器或其线路故障；发动机控制单元插头因进水接触不良或电脑内部故障。 2. 燃油系统 (1)喷油器故障 喷油器的喷油量不均、雾状不好，造成各汽缸发出的功率不平衡。常见原因有：喷油器堵塞、密封不良、喷出的燃油成线状等。 (2)燃油压力故障 油压过低，从喷油器喷出的燃油雾化状态不良或者喷出的燃油成线状，严重时只喷出油滴，喷油量减少使混合气过稀；油压过高，实际喷油量增加，使混合气过浓。常见原因有：燃油滤清器堵塞；燃油泵滤网堵塞；燃油泵的泵油能力不足；燃油泵安全阀弹簧弹力过小；进油管变形；燃油压力调节器有故障；回油管压瘪堵塞。 (3)喷油量失准 各传感器或线路故障，导致控制单元发出错误指令，使喷油量不正确，造成混合气过浓或过稀，属于怠速不稳的间接原因。具体原因有：空气流量计（或进气歧管压力传感器）故障；节气门位置传感器故障；节气门怠速开关故障；冷却液温度传感器故障；进气温度传感器故障；氧传感器失效；以上传感器的线路有断路、短路、接地故障；发动机控制单元插头因进水接触不良或电脑内部故障。 3. 点火系统 (1)点火模块与点火线圈 近些年各车型多将点火模块与点火线圈制成一体，点火模块或点火线圈有故障主要表现为高压火花弱或火花塞不点火。常见原因有：点火触发信号缺失；点火模块有故障；点火模块供电或接地线的连接松动、接触不良；初级线圈或次级线圈有故障等。 (2)火花塞与高压线 火花塞、高压线故障导致火花能量下降或失火。常见原因有：火花塞间隙不正确；火花塞电极烧蚀或损坏；火花塞电极有积炭；火花塞磁绝缘体有裂纹；高压线电阻过大；高压线绝缘外皮或插头漏电；分火头电极烧蚀或绝缘不良。 (3)点火提前角失准 由于传感器及线路故障属于引起怠速不稳的间接原因，控制单元发出错误指令，使点火提前角不正确，或造成点火提前角大范围波动。常见原因有：空气流量计或进气压力信号故障；霍尔传感器故障；冷却液温度传感器故障；进气温度传感器故障；爆震传感器故障；以上传感器的线路有断路、短路、接地故障；发动机控制单元因进水引起插头接触不良或内部电路损坏。 (4)其它原因 三元净化催化器堵塞引起怠速不稳，这种故障在高速行驶时最易发现。自动变速器、空调、转向助力器有故障会增加怠速负荷，引起怠速不稳。发动机控制单元与空调、自动变速器控制单元之间的怠速提升信号中断，在安装CAN-BUS的车辆存在总线系统故障。随着新技术、新结构的增加，引起怠速不稳的因素会更多，诊断者必须全面考虑问题。 4. 机械结构 (1)配气机构 配气机构故障导致个别汽缸的功率下降过多，从而使各汽缸功率不平衡。常见原因有：正时皮带安装位置错误，使各缸气门的开闭时间发生变化，导致配气相位失准，各汽缸燃烧不正常。气门工作面与气门座圈积炭过多，气门密封不严，使各汽缸压缩压力不一致。凸轮轴的凸轮磨损，各缸凸轮的磨损不一致导致各汽缸进入空气量不一致。气门相关件有故障，如气门推杆磨损或弯曲，摇臂磨损，气门卡住或漏气，气门弹簧折断等。 另外，装有液压挺杆的发动机，在通往汽缸盖的机油道上安装一个泄压阀，当压力高于300kPa，打开该阀。如果该阀堵塞，由于压力过高会使液压挺杆伸长过多，导致气门关闭不严。进气门背部存在大量积炭，使冷车时吸附刚喷入的燃油，而不能进入汽缸，由于混合气过稀导致冷车快怠速不稳。 (2)发动机体、活塞连杆机构 这些故障都会使个别汽缸功率下降过多，从而使各汽缸功率不平衡。常见原因有：汽缸衬垫烧蚀或损坏，造成单缸漏气或两缸之间漏气；活塞环端隙过大、对口或断裂，活塞环失去弹性；活塞环槽内积炭过多；活塞与汽缸磨损，汽缸圆度、圆柱度超差；因汽缸进水后导致的连杆弯曲，改变压缩比；燃烧室积炭会改变压缩比，积炭严重导致怠速不稳。 (3)其它原因 曲轴、飞轮、曲轴皮带轮等转动部件动平衡不合格，发动机支脚垫断裂损坏，发动机底护板因变形与油底壳相撞击等，这些原因只会造成发动机振动而不影响转速。三、故障检查与处理通过以上分析，可知引起发动机怠速不稳的原因除了一些电控方面的系统出现故障引起之外，还有可能是机械方面引起的故障。针对先简后繁的原则，可利用汽车本身的故障诊断系统诊断出由于电控系统引起的故障原因，而后再进行机械方面的诊断。在此，采用了元征X431故障诊断仪进行故障初步诊断。采用OBD接口连接好诊断仪，打开点火开关，并打开诊断仪电源，进入发动机诊断系统，读取故障代码，故障代码显示氧传感器故障。于是关闭诊断仪电源，关闭点火开关。准备对氧传感器作进一步检测。导致氧传感器出现故障的原因如下：氧传感器破碎失效；氧传感器内部进入油污或尘埃等沉积物，使传感器信号失真；使用含铅汽油使传感器中毒，而使其失效；此外，传感器橡胶垫及涂剂也会使传感器失效；电加热器故障也可能造成传感器在发动机起动及低温时不工作。图1为四线氧化锆式氧传感器与ECU的连接电路图。从图4 我们可以清楚看出氧传感器的连接方式，方便作进一步的检查。四线氧传感器的加热器负极和信号负极分别各用一根线，加热器正极和信号正极分别各用一根线。1、 氧传感器加热电阻丝电阻的检测点火开关置于“OFF”位置，拔下氧传感器的导线连接器，用万用表的档测量氧传感器接线端中加热器端子和搭铁端子间的电阻，应为440，若过大或过小，表示加热元件已损坏，应更换传感器。检查结果加热器电阻为13.6，该加热器正常。2、 氧传感器反馈电压的检测拔下氧传感器插头。使发动机以2500rmin转速运转。如图2，电压应在01V变换(频率约50次min)如电压保持在0V或1V不变，可用改变油门开度的办法人为地改变混合气浓度：突然踏下油门踏板时产生浓混合气，反馈电压应上升；突然松开油门时产生稀混合气，反馈电压应下降。如果没有变化，说明氧传感器已损坏，应更换。在检测氧传感器的反馈电压时，最好使用指针式万用表，以便直观地反应出反馈电压的变化情况，此外，电压表应是低量程和高阻抗的(阻抗太低会损坏传感器)。通过电压检测，该传感器提供的电压值为0.01V，基本可以断定氧传感器损坏，更换新件，故障排除。氧传感器是否损坏，还可用简易方法判断：拔下氧传感器的插头，从插头处（连接发动机电脑处）引入2根导线，一根接线路的信号线电路，另一根接控制单元供应电压，两只手分别拿住线路两头，如果发动机的转速发生变化即为氧传感器损坏，否则，为其它部位故障。四、维修效果：通过把有故障的氧传感器更换后，故障排除，状况良好。采用氧化锆式氧传感器的发动机，由于氧化锆式氧传感器在排气管外有气孔，使能检测大气中的氧浓度，并与排气管中废气的氧浓度进行比校，如果气孔被阻塞也是可能造成氧传感器失准，所以在检查时需对氧化锆式氧传感器的气孔进行检查，确保不堵塞。五、结束语造成发动机怠速不稳的原因有很多,有进气系统的故障,也有燃油系统的故障,而相关传感器故障引起的发动机怠速不稳也是比校多见的，比如氧传感器故障、节气门位置传感器故障等。只有充分分析造成故障原因，同时结合汽车故障诊断仪，才能较快的解决问题。六、致谢词本论文的撰写得到了杨鑫老师和潘向民老师等多位专家的指导，在此表示感谢。参考资料：1陈渝光,汽车电器与电子设备M.北京:机械工业出版社,1999 2李东江等,汽车电控系统故障检修M.北京:机械工业出版社,20013杨邦朝,简家文等.氧传感器原理与进展J.传感器世界,2002 (8)4（网络文章），电喷发动机怠速不稳故障诊断及排除，2006this type of operation for the safety technology. Without education and training in safety knowledge, shall not enter the construction site operations. To enter the construction site, you must wear a helmet, buckle chinstrap. Work at two meters high and must be fastened. When working at height, are not allowed to throw down or up the materials and tools and other objects. Persons not engaged in electrical and mechanical, prohibited the use of mechanical and electrical equipment. Building materials and components to be tidy and secure, shall not exceed the relevant provisions. Hazardous areas should be clearly marked, protective measures should be taken at night to set up a red light warning. In the operation, should adhere to their jobs, drunken operation is strictly prohibited. Special operations personnel (electricians, welders, boiler operators, blasters, lifting grid and pile drivers and commanding, shelf workers, machines, motor vehicle drivers, and so on) must be operating permits from the relevant sector professional training examinations, independent operation, operation focus, not to leave. Construction site prohibited to wear slippers, heels, skirt, sliding and studded shoes and barefoot, shirtless, and so on. Construction site of the scaffold (prohibition of the use of bamboo and wood materials setting), protective equipment, safety signs, warning signs, scaffolding wall may be supplemented, removed and need to be removed must be reinforced by the contractors agree. Construction site of the four (openings, stairs, lift head, hole) and the five-limb (balcony, framing, roofing, run (oblique) road and unloading platforms), protective measures and clearly marked. Are not allowed to sit at the feet of . Nails should be promptly removed. Drywall cut bricks are cut, no outside chopping. Preventing broken tiles fall hurt. Tools must always be mounted after good tool bag. In the Derrick (gantry) travel; in the Derrick (gantry) increased security measures are not taken to the following cleaning mortar, concrete and other debris; hanging baskets for a long time is not allowed to stop the air; after work basket must be placed in the ground, and cut off the power and lock box. Scaffolding on the Frost, snow, mud, and building waste time cleaning. Both ends of the scaffold to fasten to prevent probe Panel. Danger of overloading the scaffold: laying per square foot scaffold distributed load shall not exceed 270KN, piled up on the scaffold standard bricks of single side three storeys high. Wall removal of dangerous scaffolding; Sat down to rest on the guard rail danger; Set, dismantling scaffolding, Derrick (gantry) high, edges, vacant jobs, such as not wearing a seat belt at risk. Upper part of the ladder to fasten, antiskid measures are required in the lower part. Upper part of the ladder to hang, and lower banding. Ladder to fasten in the Middle, lower to have a non-slip steps, are not allowed to sit on it, riding moves. Altitude: personnel engaged in the Spider-man,ch zazen, budov a konstrukc, tanky a jin zsuvky prmyslov vody, krom ustanoven vodu tak, by mlo bt instalovno v oblasti s vodou k utsnn vrtu, uzavrac ventil, aby se zabrnilo velk mnostv holavch a vbunch materil do kanalizace. 9. pouit v holavch, vbunch plyn pojistn ventil a vtrac potrub, je nutn export trubice je umstn mimo a vy ne 2 metry nad budovou. (B) pouvn ohn, ohe (viz systm sprvy prce) (c) porn zazen a organizac 1. realizace prevence prvn a integrovan prevence ohe politiku, pijmout modern technologie poru a vbuchu prevence a pomoci, provdn zen podle cl. 2. zzen veden spolenosti a vedouc jednotlivch oddlen Porn bezpenost vboru, workshop zaloena porn ochrany, vedouc skupiny a nastavit dobrovolnch hasi. 3. spolenost tvaru ochrany spotebitele na pln vazek hasii, hasii formulovat pln protiporn prevence a akn pln, provdn zen podle cl, pravideln proveden publicitu porn prevence a vzdlvn a kolen, v kombinaci s oekvan porn cvien. 4. soubor stacionrn ohn uvnit spolenosti zazen, protiporn zazen mus bt v Sprva slueb, rozvoj provozn postupy a systmy zen. 5. porn zazen na serveru nastavit jasn, pstup k pohodln a bezpen msto, pravideln kontroly drby, ti (to je, pevn, fixn typ a mnostv, podle odbornk), a nem nikdo nenapadal, pachatel dle systmu ke zpracovn. 6. vechny holav a vbun ltky ve spolenosti a potenciln ped porem a vbuchem nebezpen vroby, skladovn, prodej a pouvn procesu a jeho souvisejc vybaven, psn zen. 7. kdy je ohe, pole tby okamit uspodejte do boje s ohnm, a ohledn vroby, plnovn, alarmy a ohn a adresu urit sti ohn a pinastreamlining. Four are standard visits, except as required to participate in training, no other activity. Five is to improve news reporting, for propaganda work strictly according to the regulations. Six is strictly your presentation published strictly according to the regulations. Seven is strictly thrift, required the use of vehicles and office space and corporate hospitality. 3, change the style. Propaganda and ideological work of the new situation and new requirements of the new tasks, had done a lot of fruitful work, has made many achievements, but further closer to the grass roots, close to reality, close to the masses and also inadequate innovation must continue to improve. Second, the four winds some outstanding issues 1, oppose formalism. One theory is that he didnt, with less close contact. Theoretical study of consciou