1. Catalytic Converter Laws

Rules for Replacing Converters
In 1986, the U.S. Environmental Protection Agency issued new guidelines for the construction, efficiency and installation of aftermarket catalytic converters. All CleanAir converters listed in this catalog have been designed, tested and manufactured to meet this policy.

In addition, CleanAir converter listed in this catalog is appropriate for use under the current requirements of the California Air Resources Board (C.A.R.B.).
E.P.A. guidelines state that replacement converters may be installed only in the following situations:

1. The vehicle is missing a converter
2. A state or local inspection program has determined that the existing converter needs replacement
3. Vehicles manufactured prior to 1996 must have more than 50,000 miles, and a legitimate need for replacement must be established and documented
4. In cases of OBD Il-equipped vehicles (1996 and later), the O.E. manufacturer's 8-year/80,000-mile warranty must have expired and a legitimate need for replacement must be established and documented.
Please note that Federal law prohibits removal or replacement of a properly functioning O.E. converter.

When replacement of the converter is appropriate (as outlined above), the E.P.A. further requires that:

1. It be installed in the same location as the original
2. It be the same type as the original (i.e., two-way, three-way, three-way plus air/three-way plus oxidation)
3. It be the proper model for the vehicle application as determined and specified by the manufacturer
4. It be properly connected to any existing air injection components on the vehicle
5. It be installed with any other required converter for a particular application
6. It be accompanied by a warranty information card to be completed by the installer.
http://www.magnaflow.com/02catalytic_converters/04basics/04california.asp
加州新法（2009.1.1）规定，在安装一个新的aftermarket催化器之前，下列条件必须全部满足：
（A）车辆被明确列入新售的after market催化转换器的车辆应用清单中;
（B）车辆超过7年或里程表超过70,000英里;
（C）车辆的OEM催化器保修期已过（它可以由7年或70000英里到高达15年或15万英里. 要两位安装工参考车主手册/保修手册或联系车辆制造商或其代表，以确定OEM催化器的保修期已过;
（ D ）车辆有合法的需要更换现有的转换器的理由，由安装商记录在维修发票上。如果OEM催化器已存在的，安装工在更换前必须确认它工作不正常;
（ E ）新的after market催化器必须安装在原OEM催化器被设计用于更换的同一位置。安装时催化器的前端不应超出原OEM催化器位置前端上游或下游3英寸。安装不能改变催化器原氧传感器的地点、位置或取向及上游和下游。
（ F ）新的after market催化器的安装以一换一为基础，不允许分裂为子单元。
（ G ）新的after market催化器的安装是与所有其它所需的催化转换器一起的（不能合并也不能增加）；
（ H ）安装工须填好保修卡，由客户签字，与维修发票一起，复印后寄回给制造商。
（I）安装商应保留新的after market催化器的安装文档，包括所有上述信息，并按Ttile 13, section 2222(b)(8) 提供给ARB或其代表。所有这些记录自出售或安装催化器之日起应保持四年。
also read this: http://www.epa.gov/otaq/cert/factshts/catcvrts.pdf 
转自：http://www.catalyticconverter.org/law/index.htm 
25年以上车不做smoke：
http://www.carsdirect.com/dmv/do-classic-cars-qualify-for-a-smog-exemption-in-california 
https://help.cbp.gov/app/answers/detail/a_id/278/kw/vehicle/related/1/session/L2F2LzEvdGltZS8xMzgxNjM5MTk2L3NpZC9RTjE4QkZDbA%3D%3D 
NY由2014.1.1起部分采用CA标准：http://www.californialegalconverters.com/store/Converters-California/new-york-law 
CA：http://www.magnaflow.com/02catalytic_converters/02product/02california.asp 
49州：http://www.magnaflow.com/02catalytic_converters/02product/49state.asp
dealer： http://www.magnaflow.com/api/dealer_sidebar.asp 
其它网站（49州）： http://www.discountcatalyticconverters.com/

2. Oxygen sensor

知识 http://news.m.emao.com/news/201504/7855.html  http://bbs.wenxuecity.com/auto/353770.html 常用有电压和电流输出两类，四线式其中两线为加热，电阻4-40欧。电压输出波形见下。据此，将有信号但波形不对的O2整形后输出，可能骗过MCU清除CEL信号，以此确定哪个O2出了问题。网上有在downstream O2输出加低通（0/1M与4.7u）成功的例子。对于upstream O2，我看可以加偏置可调的5倍放大电路。注意非原厂MAF=Mass Flow Sensor可能报O2错。

Cat: http://bbs.wenxuecity.com/auto/366751.html 

Sienna CAT清洗：http://bbs.wenxuecity.com/auto/402334.html Marvel Mystery oil?

06 Sienna O2: 89467-48050 Fontleft，-08040 FontRight，89465-48170 RearLeft，-08030 RearRight

清洗：http://bbs.wenxuecity.com/auto/402334.html  可临时应付检查