问：我需要更换两个传感器

只有直接测试和失败的氧气传感器才需要更换。请记住，OBD故障代码不会最终诊断出失败的零件，也不能。因此，谴责氧气传感器（或任何部分）的唯一方法是直接测试它。为了给您一个插图，如果将电线到全新的氧气传感器松动，则检查引擎灯将亮起，并且将保存“氧气传感器代码”。您可能会阅读代码并思考：“我需要一个氧气传感器。”但是，在这种情况下，氧气传感器没有错，因为传感器是全新的。相反，该代码之所以设置，是因为传感器的电线松动，因此计算机无法从传感器中读取任何数据。重点是，真正的机械师几乎永远不会根据代码替换汽车上的零件。取而代之的是，仅替换正确的零件，直接测试，一旦测试就无法满足所需的规格。该策略也可以为您节省很多钱，而且您将对汽车技术所能做到的和不能做什么更好地了解。

With regard to oxygen sensors, the ONLY technique that can be used to determine if an oxygen sensor is actually bad, and thus must be replaced, is to view it’s operation in real time on an appropriate scanner and/or hook it up to an oscilloscope. If the oxygen sensor is functioning properly, at 2,500 RPM, on a scope you will see a rough sine wave with a trough at .2, a peak at .8 volts and a frequency of about 5-7 hertz. If you see that waveform, you are good to go. If you don’t see that waveform, replace the oxygen sensor. If you see that waveform and yet the check engine light remains on and an oxygen sensor related code is still there, the problem is NOT the oxygen sensor but rather a different vehicle component. If a mechanic tells you an oxygen sensor is bad, ask him exactly what he saw on the scope. If he didn’t view the sensor on a scope, then he or she is just guessing (and wasting your time and money) as to the status of the sensor or the cause of the check engine light. To get your issue promptly and professionally resolved for you, please request a检查引擎灯诊断 - 氧气传感器波形检查响应认证的机械师将进入您的位置，并确定您的车辆需要修理什么（如果有的话）。如果您有其他疑问或疑虑，请随时重新接触万博体育入口因为我们一直在这里为您提供帮助。