2004 Audi S4 Catalytic Converters

Enhance and Protect Your 2004 Audi S4 with Quality Catalytic Converters

Maintaining the performance of your 2004 Audi S4 starts with choosing the right parts, and a high-quality Catalytic Converter helps ensure a reliable and efficient vehicle. At Advance Auto Parts, we offer Catalytic Converters specifically for the 2004 Audi S4, ensuring a perfect fit and lasting durability. Choosing to shop with Advance Auto Parts means you’re making a smart decision to prioritize both quality and reliability for your vehicle.

Affordable and Reliable Catalytic Converters for Every Budget

Finding a Catalytic Converter that combines quality with affordability is easy at Advance Auto Parts. With prices starting as low as $194.99 and an average price of $717.32, you can choose one that fits your budget while delivering the quality you expect. Our Catalytic Converters are competitively priced, ranging from $194.99 to $1,441.99, so you get value without compromising on strength or reliability.

Trusted Brands and Top-Rated Options

With 12 Catalytic Converters from 2 trusted brands in stock, Advance Auto Parts has you covered. Our Catalytic Converters for the 2004 Audi S4 have earned reviews from over 6 customers, with an average 3 stars rating across the board. Popular options include HM Grade Federal / EPA Compliant Universal Catalytic Converter, CalCat Catalytic Converter- CARB Certified, Universal / Fabrication Needed, and OEM Grade Federal / EPA Compliant Universal Catalytic Converter, starting at $194.99. Our selection includes highly regarded brands such as Magnaflow and Walker, and more, offering you top-notch reliability. For example, we have 10 Magnaflow Catalytic Converters starting at $194.99 with an average rating of 4 stars, 2 Walker options from $384.99 with a 4 stars rating.

Catalytic Converters for Your 2004 Audi S4

MagnaFlow – HM Grade Federal / EPA Compliant Universal Catalytic Converter (Part No.99235HM)

HM Grade Federal / EPA Compliant Universal Catalytic Converter

from

$261.99
MagnaFlow HM Grade Federal/EPA Compliant Universal Catalytic Converter 99235HM helps keep the check engine light off. Get the right fit for a wide array of vehicles thanks to the adaptable Universal design (cutting and welding is required). With highly corrosion resistant, stainless steel construction, you can have confidence in the quality of this catalytic converter. This replacement part is designed to meet or exceed Federal emissions requirements set forth by the EPA, complying with legal standards for OBDII Federally registered vehicles with Federal/EPA Emission systems.

Product Features:
  • Expertly formulated catalyst blend maximizes efficiency, ensuring optimal emissions control to keep your check engine light off.
  • Compact, lightweight construction enables installation in confined areas, welding is required.
  • Your trusted source for EPA-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last.
See More

MagnaFlow – OEM Grade Federal / EPA Compliant Universal Catalytic Converter (Part No.51205)

OEM Grade Federal / EPA Compliant Universal Catalytic Converter

from

$194.99
MagnaFlow OEM Grade Federal/EPA Compliant Universal Catalytic Converter 51205 helps keep the check engine light off. Get the right fit for a wide array of vehicles thanks to the adaptable Universal design (cutting and welding is required). With highly corrosion resistant, stainless steel construction, you can have confidence in the quality of this catalytic converter. This replacement part is designed to meet or exceed Federal emissions requirements set forth by the EPA, complying with legal standards for OBDII Federally registered vehicles with California or Federal/EPA Emission systems.

Product Features:
  • Expertly formulated catalyst blend maximizes efficiency, ensuring optimal emissions control to keep your check engine light off.
  • Compact, lightweight construction enables installation in confined areas, welding is required.
  • Your trusted source for EPA-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last.
See More

Walker – CalCat Catalytic Converter- CARB Certified, Universal / Fabrication Needed (Part No.81652)

CalCat Catalytic Converter- CARB Certified, Universal / Fabrication Needed

from

$384.99
Designed, tested and validated for assured compliance to meet CARB standards, Walker® CalCat® Universal Catalytic Converters are available for OBDII (1996 and newer) and non-OBD (1995 and older) vehicles.

Product Features:
  • CARB COMPLIANT — For use on OBDII vehicles, 1996 and newer and non-OBD 1995 and older. Legal for sale in CA, CO, NY & other states requiring CARB-compliant replacement converters. Consult your state’s aftermarket converter regulations.
  • SUPERIOR TECHNOLOGY — Optimal high technology washcoat formulated to deliver superior performance (as compared to EPA-compliant converters)
  • CONSISTENT PERFORMANCE — Utilizes a precise OE-style coating process to apply catalyst material to the substrate, providing consistent performance for assured emissions compliance
  • DURABLE — Features stainless-steel body with aluminized pipe and heat shields for durability
  • FLEXIBLE SOLUTION — Customizable design features expandable bushings for easy fitment and may require specialized fabrication and/or welding for installation
  • BUY WITH CONFIDENCE — Backed by Walker’s 50,000-mile/80,000-kilometer emissions and structural integrity warranty
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MagnaFlow – California Grade CARB Compliant Direct-Fit Catalytic Converter (Part No.441096)

California Grade CARB Compliant Direct-Fit Catalytic Converter

from

$1441.99
Keep the check engine light off with MagnaFlow California Grade CARB Compliant Direct-Fit Catalytic Converter 441096. With features including free-flowing mandrel-bent tubing and highly corrosion resistant stainless steel construction, easily install this spun body converter yourself using the proper tools, no cutting or welding required. MagnaFlow’s state-of-the-art metrology department uses the latest 3D scanning systems during research and development, so you can be confident that your new part will fit and function like the original equipment. By replicating the OE spun body design, the single laser fusion weld greatly reduces the possibility of a leak, and our compact, low-mass design also allows for greater thermal efficiency. Designed to fit the 2004-2006 Audi S4, 2004 Audi Allroad Quattro, and more, this direct-fit catalytic converter also interchanges with OE parts 8E0 254 554 QX and 8E0 254 551 QX. This replacement part is designed to meet or exceed California Air Resource Board requirements, and has undergone additional testing to comply with CARB guidelines to allow for legal use in California and CARB restricted states, for the listed vehicles.

Product Features:
  • Expertly crafted to replicate OEM-like flow dynamics, maintaining factory performance and fuel efficiency.
  • Simplifies installation with essential gaskets and hardware being included in the box.
  • Your trusted source for CARB-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last.
See More

MagnaFlow – OEM Grade Federal / EPA Compliant Direct-Fit Catalytic Converter (Part No.49872)

OEM Grade Federal / EPA Compliant Direct-Fit Catalytic Converter

from

$1157.99
Keep the check engine light off with MagnaFlow OEM Grade Federal/EPA Compliant Direct-Fit Catalytic Converter 49872. With features including free-flowing mandrel-bent tubing and highly corrosion resistant stainless steel construction, easily install this spun body converter yourself using the proper tools, no cutting or welding required. MagnaFlow’s state-of-the-art metrology department uses the latest 3D scanning systems during research and development, so you can be confident that your new part will fit and function like the original equipment. By replicating the OE spun body design, the single laser fusion weld greatly reduces the possibility of a leak, and our compact, low-mass design also allows for greater thermal efficiency. This direct-fit catalytic converter is designed specifically for the 2004-2009 Audi S4 and interchanges with OE parts 8E0 254 554 PX and 8E0 254 551 PX. Hardware is included to eliminate the hassle of working with corroded factory parts. This replacement part is designed to meet or exceed Federal emissions requirements set forth by the EPA, complying with legal standards for OBDII Federally registered vehicles with California or Federal/EPA Emission systems.

Product Features:
  • Expertly crafted to replicate OEM-like flow dynamics, maintaining factory performance and fuel efficiency.
  • Simplifies installation with essential gaskets and hardware being included in the box.
  • Your trusted source for EPA-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last.
See More

MagnaFlow – OEM Grade Federal / EPA Compliant Direct-Fit Catalytic Converter (Part No.49917)

OEM Grade Federal / EPA Compliant Direct-Fit Catalytic Converter

from

$1012.99
Keep the check engine light off with MagnaFlow OEM Grade Federal/EPA Compliant Direct-Fit Catalytic Converter 49917. With features including free-flowing mandrel-bent tubing and highly corrosion resistant stainless steel construction, easily install this spun body converter yourself using the proper tools, no cutting or welding required. MagnaFlow’s state-of-the-art metrology department uses the latest 3D scanning systems during research and development, so you can be confident that your new part will fit and function like the original equipment. By replicating the OE spun body design, the single laser fusion weld greatly reduces the possibility of a leak, and our compact, low-mass design also allows for greater thermal efficiency. This direct-fit catalytic converter is designed specifically for the 2004-2009 Audi S4 and interchanges with OE parts 8E0 254 505 SX and 8E0 254 502 JX. This replacement part is designed to meet or exceed Federal emissions requirements set forth by the EPA, complying with legal standards for OBDII Federally registered vehicles with California or Federal/EPA Emission systems.

Product Features:
  • Expertly crafted to replicate OEM-like flow dynamics, maintaining factory performance and fuel efficiency.
  • Simplifies installation with essential gaskets and hardware being included in the box.
  • Your trusted source for EPA-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last.
See More

MagnaFlow – OEM Grade Federal / EPA Compliant Direct-Fit Catalytic Converter (Part No.49918)

OEM Grade Federal / EPA Compliant Direct-Fit Catalytic Converter

from

$980.99
Keep the check engine light off with MagnaFlow OEM Grade Federal/EPA Compliant Direct-Fit Catalytic Converter 49918. With features including free-flowing mandrel-bent tubing and highly corrosion resistant stainless steel construction, easily install this spun body converter yourself using the proper tools, no cutting or welding required. MagnaFlow’s state-of-the-art metrology department uses the latest 3D scanning systems during research and development, so you can be confident that your new part will fit and function like the original equipment. By replicating the OE spun body design, the single laser fusion weld greatly reduces the possibility of a leak, and our compact, low-mass design also allows for greater thermal efficiency. This direct-fit catalytic converter is designed specifically for the 2004-2009 Audi S4 and interchanges with OE parts 8E0 254 554 QX and 8E0 254 551 QX. This replacement part is designed to meet or exceed Federal emissions requirements set forth by the EPA, complying with legal standards for OBDII Federally registered vehicles with California or Federal/EPA Emission systems.

Product Features:
  • Expertly crafted to replicate OEM-like flow dynamics, maintaining factory performance and fuel efficiency.
  • Simplifies installation with essential gaskets and hardware being included in the box.
  • Your trusted source for EPA-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last.
See More

MagnaFlow – HM Grade Federal / EPA Compliant Direct-Fit Catalytic Converter (Part No.24317)

HM Grade Federal / EPA Compliant Direct-Fit Catalytic Converter

from

$964.99
Keep the check engine light off with MagnaFlow HM Grade Federal/EPA Compliant Direct-Fit Catalytic Converter 24317. With features including free-flowing mandrel-bent tubing and highly corrosion resistant stainless steel construction, easily install this spun body converter yourself using the proper tools, no cutting or welding required. MagnaFlow’s state-of-the-art metrology department uses the latest 3D scanning systems during research and development, so you can be confident that your new part will fit and function like the original equipment. By replicating the OE spun body design, the single laser fusion weld greatly reduces the possibility of a leak, and our compact, low-mass design also allows for greater thermal efficiency. This direct-fit catalytic converter is designed specifically for the 2004-2009 Audi S4 and interchanges with OE parts 8E0 254 505 SX and 8E0 254 502 JX. This replacement part is designed to meet or exceed Federal emissions requirements set forth by the EPA, complying with legal standards for OBDII Federally registered vehicles with Federal/EPA Emission systems.

Product Features:
  • Expertly crafted to replicate OEM-like flow dynamics, maintaining factory performance and fuel efficiency.
  • Simplifies installation with essential gaskets and hardware being included in the box.
  • Your trusted source for EPA-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last.
See More

MagnaFlow – HM Grade Federal / EPA Compliant Direct-Fit Catalytic Converter (Part No.24318)

HM Grade Federal / EPA Compliant Direct-Fit Catalytic Converter

from

$933.99
Keep the check engine light off with MagnaFlow HM Grade Federal/EPA Compliant Direct-Fit Catalytic Converter 24318. With features including free-flowing mandrel-bent tubing and highly corrosion resistant stainless steel construction, easily install this spun body converter yourself using the proper tools, no cutting or welding required. MagnaFlow’s state-of-the-art metrology department uses the latest 3D scanning systems during research and development, so you can be confident that your new part will fit and function like the original equipment. By replicating the OE spun body design, the single laser fusion weld greatly reduces the possibility of a leak, and our compact, low-mass design also allows for greater thermal efficiency. This direct-fit catalytic converter is designed specifically for the 2004-2009 Audi S4 and interchanges with OE parts 8E0 254 554 QX and 8E0 254 551 QX. This replacement part is designed to meet or exceed Federal emissions requirements set forth by the EPA, complying with legal standards for OBDII Federally registered vehicles with Federal/EPA Emission systems.

Product Features:
  • Expertly crafted to replicate OEM-like flow dynamics, maintaining factory performance and fuel efficiency.
  • Simplifies installation with essential gaskets and hardware being included in the box.
  • Your trusted source for EPA-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last.
See More

MagnaFlow – California Grade CARB Compliant Universal Catalytic Converter (Part No.441204)

California Grade CARB Compliant Universal Catalytic Converter

from

$585.99
MagnaFlow California Grade CARB Compliant Universal Catalytic Converter 441204 helps keep the check engine light off. Get the right fit for a wide array of vehicles thanks to the adaptable Universal design (cutting and welding is required). With highly corrosion resistant, stainless steel construction, you can have confidence in the quality of this catalytic converter. This replacement part is designed to meet or exceed California Air Resource Board requirements, and has undergone additional testing to comply with CARB guidelines to allow for legal use in California and CARB restricted states, for the listed vehicles.

Product Features:
  • Expertly formulated catalyst blend maximizes efficiency, ensuring optimal emissions control to keep your check engine light off.
  • Compact, lightweight construction enables installation in confined areas, welding is required.
  • Your trusted source for CARB-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last.
See More

Walker – CalCat Catalytic Converter- CARB Certified, Universal / Fabrication Needed (Part No.81804)

CalCat Catalytic Converter- CARB Certified, Universal / Fabrication Needed

from

$488.99
Designed, tested and validated for assured compliance to meet CARB standards, Walker CalCat Universal Catalytic Converters are available for OBDII (1996 and newer) and non-OBD (1995 and older) vehicles.

Product Features:
  • CARB COMPLIANT — For use on OBDII vehicles, 1996 and newer and non-OBD 1995 and older. Legal for sale in CA, CO, NY & other states requiring CARB-compliant replacement converters. Consult your state’s aftermarket converter regulations.
  • SUPERIOR TECHNOLOGY — Optimal high technology washcoat formulated to deliver superior performance (as compared to EPA-compliant converters)
  • CONSISTENT PERFORMANCE — Utilizes a precise OE-style coating process to apply catalyst material to the substrate, providing consistent performance for assured emissions compliance
  • DURABLE — Features stainless-steel body with aluminized pipe and heat shields for durability
  • FLEXIBLE SOLUTION — Customizable design features expandable bushings for easy fitment and may require specialized fabrication and/or welding for installation
See More

MagnaFlow – OEM Grade Federal / EPA Compliant Universal Catalytic Converter (Part No.51235)

OEM Grade Federal / EPA Compliant Universal Catalytic Converter

from

$197.99
MagnaFlow OEM Grade Federal/EPA Compliant Universal Catalytic Converter 51235 helps keep the check engine light off. Get the right fit for a wide array of vehicles thanks to the adaptable Universal design (cutting and welding is required). With highly corrosion resistant, stainless steel construction, you can have confidence in the quality of this catalytic converter. This replacement part is designed to meet or exceed Federal emissions requirements set forth by the EPA, complying with legal standards for OBDII Federally registered vehicles with California or Federal/EPA Emission systems.

Product Features:
  • Expertly formulated catalyst blend maximizes efficiency, ensuring optimal emissions control to keep your check engine light off.
  • Compact, lightweight construction enables installation in confined areas, welding is required.
  • Your trusted source for EPA-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last.
See More

FAQs for 2004 Audi S4 Catalytic Converters

Which Catalytic Converters are the top sellers for the 2004 Audi S4?

Out of 12 Catalytic Converters that fit 2004 Audi S4s, the following parts are the top sellers:
CalCat Catalytic Converter- CARB Certified, Universal / Fabrication Needed
from $384.99
This product is not rated
CalCat Catalytic Converter- CARB Certified, Universal / Fabrication Needed
Catalytic Converters
OEM Grade Federal / EPA Compliant Universal Catalytic Converter
from $194.99
This product is not rated
OEM Grade Federal / EPA Compliant Universal Catalytic Converter
Catalytic Converters

How can I make sure that a part will be compatible with my 2004 Audi S4?

Our Audi S4 aftermarket and OEM parts are designed specifically for the 2004 model. You can always find your specific fitment and compatibility for your 2004 Audi on an individual product page.

What is the price range for 2004 Audi S4 Catalytic Converters?

The range of prices of Catalytic Converters for the 2004 Audi S4 goes from $194.99 up to $1,441.99 for the most premium parts.

What is the average price of a 2004 Audi S4 Catalytic Converter?

2004 Audi S4 Catalytic Converters average $717.32 for our selection of OEM and aftermarket parts. Keep in mind the variety of brands we offer, such as Magnaflow Walker, and more, so you are likely to find a wide range of prices across a variety of brands and products.

Does Advance Auto Parts sell Catalytic Converters for other Audi S4 model years?

Yes, we currently stock Catalytic Converters for 18 model years of Audi S4s, from 1992 to 2016. Model years 2016, 2015, 2014, 2013, 2012, 2011, 2010, 2009, and 2008 are the most popular for Catalytic Converter purchases.

Can I get help with 2004 Audi S4 Catalytic Converter orders?

Contact our customer support team, by chat or phone, through the help desk page, where you can find instant answers about Audi Catalytic Converters and more.

What is your return policy for Audi S4 Catalytic Converters?

Advance Auto Parts keeps returns simple. For new Audi S4 Catalytic Converters and accessories, your online orders can be returned, in their original condition, within 45 days. For requirements, see the returns page.