MagnaFlow Catalytic Converter - E46 323i/328i M52TU Bank 2
Affordable replacement catalytic converter for states that do NOT use California Emissions
This E46 323i/328i catalytic converter is a direct replacement for the original cat and is approved for use in 46 states. MagnaFlow catalytic converters are a Direct-Fit design for each model and emissions spec, ensuring long-lasting quality and emissions compliance. Unlike cheap aftermarket cats that may not even be legal in your state, MagnaFlow Heavy Metal (HM) cats meet federal EPA emissions requirements for performance, quality, durability, and warranty.
MagnaFlow does not simply fit a universal cat to car-specific pipes. They have multiple grades of precious metals and catalytic material so each application gets the correct and best-performing catalytic reaction to achieve emissions requirements. This is a HM-grade cat using premium Heavy Metals to meet BMW's emissions targets. Each piece is made with stainless steel mandrel-bent piping, laser-cut flanges, and OE-style connections. Most systems include new gaskets or clamps. This is an aftermarket piece priced significantly lower than the Genuine BMW equivalent. Although Genuine BMW will be a higher quality overall it comes with a price tag typically 3-5x higher. MagnaFlow EPA-approved cats have a 2 year or 25,000 mile warranty on the catalytic material and a 5 year or 50,000 mile warranty on materials and workmanship.
Catalytic converters rarely fail on their own. In most cases, another issue has caused the catalytic material to be contaminated, overheated, or damaged, leading to failure. The most typical failure comes from a failed primary/front O2 sensor, which cause the engine to run rich (reducing fuel economy), which also melts the catalyst. Replacing your failed catalyst without solving the root cause of failure will void any warranty and significantly reduce lifespan of the replacement catalyst. It is the customer's responsibility to diagnose and determine the root cause of a catalyst-related engine code. Before spending thousands of dollars on a new catalytic converter, make sure you have considered and investigated all other potential sources for your fault codes - oxygen (O2) sensors, cooling system, intake or exhaust leaks, fuel injection, vacuum, secondary air system, and other emissions-related equipment. Returns of this product are limited to quality and workmanship issues only.
Federal vs California Spec. Catalytic converters must be matched to the vehicle build specification and/or the region where it will be used. Using a non-California cat on a California-spec car will result in failure of emissions inspection and possibly even poor drivability, fault codes, and a check engine light for incompatible parts. Your vehicle spec can be found on an emissions label on the underside of your hood. California-spec cats are more expensive but have premium catalytic material and a longer warranty.
California (CARB grade or CARB certified): you must use a California-spec cat. A California-spec cat can be used in all 50 states, regardless of original spec.
Colorado, Maine, or New York: state law requires a CARB-certified cat for all new sales beginning January 1, 2023, regardless if the car was built as a “California version” or not. The previous "OEM grade" will no longer be accepted in these states.
All other states (Federal) (MagnaFlow HM or Standard grades): the “Federal” spec is acceptable, however, using a non-California cat on a California-spec car may cause poor drivability, fault codes, and a check engine light for incompatible parts.
E46 (99-05) > 323Ci
E46 (99-05) > 323i
E46 (99-05) > 328Ci
E46 (99-05) > 328i