Seat Mii Catalytic Converter (2011-2021)

The catalytic converter in a SEAT Mii 1.0 12v engine is a key component of the exhaust system designed to reduce harmful emissions. It helps convert toxic gases from combustion into less harmful substances, ensuring the vehicle complies with environmental standards such as Euro 5 and Euro 6 depending on the model year.

This catalytic converter is primarily designed for SEAT Mii 1.0 12v models with engine codes CHYA (60 PS) and CHYB (75 PS), produced mainly between 2011 and 2015. Some Euro 6 versions are also compatible with related models such as Skoda Citigo and Volkswagen up!.

Original Equipment (OE) part numbers include:

• 1S0253053BX
• 2S1364164BY

Comparison reference numbers used in the market are:

• Bosal 090-812
• EEC VK6126T
• Walker 28349

These codes help identify the correct catalytic converter type for your vehicle's engine and Euro standard.

Common signs of a faulty or clogged catalytic converter include:

• Reduced engine performance and power loss
• Unusual exhaust odors similar to rotten eggs
• Check engine light illuminating with codes such as P0420
• Irregular engine idling or increased fuel consumption

If you notice these symptoms, have your vehicle inspected by a qualified professional who can perform a diagnostic check and recommend whether a replacement is needed.

Yes, a DIY replacement is feasible if you follow proper steps and have the correct tools. General guidance includes:

• Diagnosing the fault accurately
• Careful removal of the old catalytic converter, avoiding damage to sensors or exhaust parts
• Installing the new converter using a proper mounting kit supplied with the part
• Replacing the Lambda (oxygen) sensor if recommended

It's advised to refer to step-by-step illustrated manuals and video tutorials specific to the SEAT Mii 1.0 engine or similar models to ensure correct installation and avoid common errors.

When selecting a catalytic converter, consider the following details:

• Ensure compatibility with your vehicle’s engine code (CHYA or CHYB) and production year
• Look for compliance with emission standards such as Euro 5 or Euro 6 and possession of E-mark certification
• Choose a new, original condition catalytic converter, ideally made of stainless steel with a high-quality monolith for durability
• Check if the product includes mounting hardware, installation instructions, and homologation certification

This approach helps maintain original car performance, emission compliance, and ensures reliability.

New catalytic converters for SEAT Mii 1.0 models generally range between approximately 200 to 500 Euros depending on the supplier and specifications.

For used catalytic converters, scrap value prices as of early 2026 are roughly:

• Used petrol catalytic converters: 49 to 59 USD
• Used ceramic catalytic converters: 44 to 53 USD

Note that scrap prices fluctuate with market demand and condition of the part.

Krosfou offers reliable delivery services with options including standard and express shipping across Europe and internationally. Key details include:

• Same-day dispatch for in-stock orders placed before noon
• Standard delivery within 1 to 6 working days in Europe, free above a certain order amount
• Express delivery available within 24 to 48 hours
• Free returns within 30 days for unused products in original packaging
• Three-year warranty covering up to 100,000 km usage on new catalytic converters

Krosfou guarantees high-quality, stainless steel catalytic converters manufactured in Europe with TÜV certification ensuring compliance with all relevant regulations and durable performance for your SEAT Mii engine.