Audi S4 Catalytic Converters

Your One-Stop Shop For Trusted Audi S4 Catalytic Converters

If you’re in search of Audi S4 Catalytic Converters aftermarket or OEM parts, consider your search over! Advance Auto Parts carries 34 Catalytic Converters from top brands with prices ranging from $106.99 to $1,512.00.

Beyond great prices, we stock trusted brands manufacturing all types of Catalytic Converters for your Audi S4.

And don’t forget to read customer reviews across all Catalytic Converters categories in our catalog. Buy with confidence by leveraging past customer experiences of our aftermarket and OEM parts.

At Advance Auto Parts, we don’t think top quality Catalytic Converters have to cost top dollar, and we prove it. Browse our top Audi S4 Catalytic Converters below, order online to ship to your home, or head into your nearest Advance Auto Parts location to get started.

Please Select your Vehicle to See Exact Fit Parts

Essential Audi S4 Catalytic Converters

MagnaFlow – MagnaFlow Hm Grade Federal / Epa Compliant Universal Catalytic Converter, 99205HM (Part No.99205HM)

MagnaFlow Hm Grade Federal / Epa Compliant Universal Catalytic Converter, 99205HM

from

$196.99
Keep the check engine light off with MagnaFlow HM Grade Federal/EPA Compliant Universal Catalytic Converter 99205HM. The Universal design allows the part to fit a wide array of vehicles, and the stainless steel construction of this catalytic converter is highly resistant to corrosion. 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 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.
See More

Walker – "Walker CalCat CARB Universal Catalytic Converter 2"" Inlet (ID) 2"" Outlet (ID), 81660" (Part No.81660)

"Walker CalCat CARB Universal Catalytic Converter 2"" Inlet (ID) 2"" Outlet (ID), 81660"

from

$561.99
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. Walker CalCat catalytic converters are thoroughly tested to ensure they meet CARB performance requirements.
See More

MagnaFlow – MagnaFlow Oem Grade Federal / Epa Compliant Direct-Fit Catalytic Converter, 49136 (Part No.49136)

MagnaFlow Oem Grade Federal / Epa Compliant Direct-Fit Catalytic Converter, 49136

from

$1143.00
Keep the check engine light off with MagnaFlow OEM Grade Federal/EPA Compliant Direct-Fit Catalytic Converter 49136. With features including free-flowing mandrel-bent tubing and highly corrosion resistant stainless steel construction, easily install this 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 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. MagnaFlow 49136 includes (1) Nut, (3) Bolts, (1) O2 Port Plug, (1) Flange Gasket and interchanges with OE parts 8K0 254 250 KX, 8K0 254 250 PX, 8K0 254 253 AX, 8K0 254 253 K. 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.
See More

MagnaFlow – MagnaFlow California Grade Carb Compliant Direct-Fit Catalytic Converter, 441093 (Part No.441093)

MagnaFlow California Grade Carb Compliant Direct-Fit Catalytic Converter, 441093

from

$1512.00
Keep the check engine light off with MagnaFlow California Grade CARB Compliant Direct-Fit Catalytic Converter 441093. With features including free-flowing mandrel-bent tubing and highly corrosion resistant stainless steel construction, easily install this 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 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 to fit the 2001-2002 Audi S4 2.7L & 2001-2002 Audi Allroad Quattro 2.7L. MagnaFlow 441093 includes (1) Flange Gasket and interchanges with OE parts 8E0 253 057 HX. 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.
See More

MagnaFlow – MagnaFlow Oem Grade Federal / Epa Compliant Direct-Fit Catalytic Converter, 49918 (Part No.49918)

MagnaFlow Oem Grade Federal / Epa Compliant Direct-Fit Catalytic Converter, 49918

from

$1017.00
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 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 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 to fit the 2004-2009 Audi S4 4.2L. MagnaFlow 49918 interchanges with OE parts 8E0 254 551 QX, 8E0 254 554 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.
See More

Walker – "Walker CalCat CARB Universal Catalytic Converter 2.25"" Inlet (ID) 2.25"" Outlet (ID), 81652" (Part No.81652)

"Walker CalCat CARB Universal Catalytic Converter 2.25"" Inlet (ID) 2.25"" Outlet (ID), 81652"

from

$423.99
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. Walker CalCat catalytic converters are thoroughly tested to ensure they meet CARB performance requirements.
See More

MagnaFlow – MagnaFlow Oem Grade Federal / Epa Compliant Direct-Fit Catalytic Converter, 49917 (Part No.49917)

MagnaFlow Oem Grade Federal / Epa Compliant Direct-Fit Catalytic Converter, 49917

from

$1051.00
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 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 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 to fit the 2004-2009 Audi S4 4.2L. MagnaFlow 49917 interchanges with OE parts 8E0 254 502 JX, 8E0 254 505 SX. 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.
See More

MagnaFlow – MagnaFlow Hm Grade Federal / Epa Compliant Universal Catalytic Converter, 99305HM (Part No.99305HM)

MagnaFlow Hm Grade Federal / Epa Compliant Universal Catalytic Converter, 99305HM

from

$204.99
Keep the check engine light off with MagnaFlow HM Grade Federal/EPA Compliant Universal Catalytic Converter 99305HM. The Universal design allows the part to fit a wide array of vehicles, and the stainless steel construction of this catalytic converter is highly resistant to corrosion. 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 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.
See More

MagnaFlow – MagnaFlow California Grade Carb Compliant Universal Catalytic Converter, 5411275 (Part No.5411275)

MagnaFlow California Grade Carb Compliant Universal Catalytic Converter, 5411275

from

$737.99
Keep the check engine light off with MagnaFlow California Grade CARB Compliant Universal Catalytic Converter 5411275. The Universal design allows the part to fit a wide array of vehicles, and the stainless steel construction of this catalytic converter is highly resistant to corrosion. 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 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.
See More

MagnaFlow – MagnaFlow Hm Grade Federal / Epa Compliant Universal Catalytic Converter, 99005HM (Part No.99005HM)

MagnaFlow Hm Grade Federal / Epa Compliant Universal Catalytic Converter, 99005HM

from

$242.99
Keep the check engine light off with MagnaFlow HM Grade Federal/EPA Compliant Universal Catalytic Converter 99005HM. The Universal design allows the part to fit a wide array of vehicles, and the stainless steel construction of this catalytic converter is highly resistant to corrosion. 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 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.
See More

MagnaFlow – MagnaFlow Oem Grade Federal / Epa Compliant Universal Catalytic Converter, 51005 (Part No.51005)

MagnaFlow Oem Grade Federal / Epa Compliant Universal Catalytic Converter, 51005

from

$252.99
Keep the check engine light off with MagnaFlow OEM Grade Federal/EPA Compliant Universal Catalytic Converter 51005. The Universal design allows the part to fit a wide array of vehicles, and the stainless steel construction of this catalytic converter is highly resistant to corrosion. The single laser fusion welds greatly reduces the possibility of a leak, and our compact, low-mass design also allows for greater thermal efficiency. 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.
See More

MagnaFlow – MagnaFlow California Grade Carb Compliant Universal Catalytic Converter, 5421205 (Part No.5421205)

MagnaFlow California Grade Carb Compliant Universal Catalytic Converter, 5421205

from

$367.99
Keep the check engine light off with MagnaFlow California Grade CARB Compliant Universal Catalytic Converter 5421205. The Universal design allows the part to fit a wide array of vehicles, and the stainless steel construction of this catalytic converter is highly resistant to corrosion. 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 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.
See More

MagnaFlow – MagnaFlow Oem Grade Federal / Epa Compliant Direct-Fit Catalytic Converter, 49135 (Part No.49135)

MagnaFlow Oem Grade Federal / Epa Compliant Direct-Fit Catalytic Converter, 49135

from

$932.99
Keep the check engine light off with MagnaFlow OEM Grade Federal/EPA Compliant Direct-Fit Catalytic Converter 49135. With features including free-flowing mandrel-bent tubing and highly corrosion resistant stainless steel construction, easily install this 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 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. MagnaFlow 49135 includes (1) Nut, (3) Bolts, (1) O2 Port Plug, (1) Flange Gasket and interchanges with OE parts 8K0 254 200 DX, 8K0 254 200 FX, 8K0 254 200 KX, 8K0 254 200 PX, 8K0 254 200 SX, 8K0 254 202 CX. 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.
See More

MagnaFlow – MagnaFlow Oem Grade Federal / Epa Compliant Universal Catalytic Converter, 51235 (Part No.51235)

MagnaFlow Oem Grade Federal / Epa Compliant Universal Catalytic Converter, 51235

from

$214.99
Keep the check engine light off with MagnaFlow OEM Grade Federal/EPA Compliant Universal Catalytic Converter 51235. The Universal design allows the part to fit a wide array of vehicles, and the stainless steel construction of this catalytic converter is highly resistant to corrosion. The single laser fusion welds greatly reduces the possibility of a leak, and our compact, low-mass design also allows for greater thermal efficiency. 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.
See More

Walker – "Walker CalCat CARB Universal Catalytic Converter 2"" Inlet (ID) 2"" Outlet (ID), 81101" (Part No.81101)

"Walker CalCat CARB Universal Catalytic Converter 2"" Inlet (ID) 2"" Outlet (ID), 81101"

from

$506.99
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. Walker CalCat catalytic converters are thoroughly tested to ensure they meet CARB performance requirements.
See More

MagnaFlow – MagnaFlow California Grade Carb Compliant Universal Catalytic Converter, 5421206 (Part No.5421206)

MagnaFlow California Grade Carb Compliant Universal Catalytic Converter, 5421206

from

$367.99
Keep the check engine light off with MagnaFlow California Grade CARB Compliant Universal Catalytic Converter 5421206. The Universal design allows the part to fit a wide array of vehicles, and the stainless steel construction of this catalytic converter is highly resistant to corrosion. 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 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.
See More

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

MagnaFlow California Grade Carb Compliant Universal Catalytic Converter, 441204

from

$637.99
Keep the check engine light off with MagnaFlow California Grade CARB Compliant Universal Catalytic Converter 441204. The Universal design allows the part to fit a wide array of vehicles, and the stainless steel construction of this catalytic converter is highly resistant to corrosion. 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 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.
See More

MagnaFlow – MagnaFlow Oem Grade Federal / Epa Compliant Direct-Fit Catalytic Converter, 49916 (Part No.49916)

MagnaFlow Oem Grade Federal / Epa Compliant Direct-Fit Catalytic Converter, 49916

from

$841.99
Keep the check engine light off with MagnaFlow OEM Grade Federal/EPA Compliant Direct-Fit Catalytic Converter 49916. With features including free-flowing mandrel-bent tubing and highly corrosion resistant stainless steel construction, easily install this 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 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 to fit the 2000-2002 Audi S4 2.7L. MagnaFlow 49916 includes (1) Flange Gasket and interchanges with OE parts 8E0 253 058 BX. 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.
See More

MagnaFlow – MagnaFlow California Grade Carb Compliant Universal Catalytic Converter, 444134 (Part No.444134)

MagnaFlow California Grade Carb Compliant Universal Catalytic Converter, 444134

from

$362.99
Keep the check engine light off with MagnaFlow California Grade CARB Compliant Universal Catalytic Converter 444134. The Universal design allows the part to fit a wide array of vehicles, and the stainless steel construction of this catalytic converter is highly resistant to corrosion. 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 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.
See More

MagnaFlow – MagnaFlow Oem Grade Federal / Epa Compliant Universal Catalytic Converter, 51204 (Part No.51204)

MagnaFlow Oem Grade Federal / Epa Compliant Universal Catalytic Converter, 51204

from

$213.99
Keep the check engine light off with MagnaFlow OEM Grade Federal/EPA Compliant Universal Catalytic Converter 51204. The Universal design allows the part to fit a wide array of vehicles, and the stainless steel construction of this catalytic converter is highly resistant to corrosion. The single laser fusion welds greatly reduces the possibility of a leak, and our compact, low-mass design also allows for greater thermal efficiency. 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.
See More

MagnaFlow – MagnaFlow Standard Grade Federal / Epa Compliant Universal Catalytic Converter, 53004 (Part No.53004)

MagnaFlow Standard Grade Federal / Epa Compliant Universal Catalytic Converter, 53004

from

$106.99
Keep the check engine light off with MagnaFlow Standard Grade Federal/EPA Compliant Universal Catalytic Converter 53004. Get the right fit for a wide array of vehicles thanks to the adaptable Universal design. 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 pre-OBDII Federally registered vehicles.
See More

MagnaFlow – MagnaFlow Oem Grade Federal / Epa Compliant Direct-Fit Catalytic Converter, 49915 (Part No.49915)

MagnaFlow Oem Grade Federal / Epa Compliant Direct-Fit Catalytic Converter, 49915

from

$891.99
Keep the check engine light off with MagnaFlow OEM Grade Federal/EPA Compliant Direct-Fit Catalytic Converter 49915. With features including free-flowing mandrel-bent tubing and highly corrosion resistant stainless steel construction, easily install this 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 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 to fit the 2000-2002 Audi S4 2.7L. MagnaFlow 49915 includes (1) Flange Gasket and interchanges with OE parts 8E0 253 057 HX. 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.
See More

MagnaFlow – MagnaFlow California Grade Carb Compliant Universal Catalytic Converter, 444005 (Part No.444005)

MagnaFlow California Grade Carb Compliant Universal Catalytic Converter, 444005

from

$404.99
Keep the check engine light off with MagnaFlow California Grade CARB Compliant Universal Catalytic Converter 444005. The Universal design allows the part to fit a wide array of vehicles, and the stainless steel construction of this catalytic converter is highly resistant to corrosion. 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 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.
See More

MagnaFlow – MagnaFlow California Grade Carb Compliant Universal Catalytic Converter, 441005 (Part No.441005)

MagnaFlow California Grade Carb Compliant Universal Catalytic Converter, 441005

from

$548.99
Keep the check engine light off with MagnaFlow California Grade CARB Compliant Universal Catalytic Converter 441005. The Universal design allows the part to fit a wide array of vehicles, and the stainless steel construction of this catalytic converter is highly resistant to corrosion. 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 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.
See More

MagnaFlow – MagnaFlow California Grade Carb Compliant Universal Catalytic Converter, 444206 (Part No.444206)

MagnaFlow California Grade Carb Compliant Universal Catalytic Converter, 444206

from

$412.99
Keep the check engine light off with MagnaFlow California Grade CARB Compliant Universal Catalytic Converter 444206. The Universal design allows the part to fit a wide array of vehicles, and the stainless steel construction of this catalytic converter is highly resistant to corrosion. 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 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.
See More

Catalytic Converters Brands You Can Trust For Your Audi S4

2 trusted brands of Catalytic Converters line our shelves, ready to help keep your Audi S4 running smooth. Below are some of the most popular brands and their top Catalytic Converters offerings:

Popular MagnaFlow Catalytic Converters

MagnaFlow products for the Audi S4 span several categories. Some of the highest-rated MagnaFlow Catalytic Converters that will fit your Audi S4 are:

Top Audi S4 Catalytic Converters from MagnaFlow

Your Audi S4 will be purring again thanks to MagnaFlow brand Catalytic Converters available for online order or in-store pick up. Popular MagnaFlow parts include:

Most Purchased Audi S4 Catalytic Converters from MagnaFlow

When you buy the most frequently purchased MagnaFlow brand Catalytic Converters, you can be confident it will be the right part for your Audi S4. Here are the MagnaFlow Catalytic Converters Advanced Auto customers buy the most:

FAQs for Audi S4 Catalytic Converters

What are the most purchased Catalytic Converters for the Audi S4?

Out of 34 Catalytic Converters for the Audi S4, the most popular in our inventory are:
"Walker CalCat CARB Universal Catalytic Converter 2"" Inlet (ID) 2"" Outlet (ID), 81101"
from $506.99
This product is not rated
"Walker CalCat CARB Universal Catalytic Converter 2"" Inlet (ID) 2"" Outlet (ID), 81101"
Catalytic Converters
MagnaFlow Oem Grade Federal / Epa Compliant Universal Catalytic Converter, 51205
from $213.99
This product is not rated
MagnaFlow Oem Grade Federal / Epa Compliant Universal Catalytic Converter, 51205
Catalytic Converters

What are the top-rated Audi S4 Catalytic Converters?

Top-rated Catalytic Converters for your Audi S4 based on customer reviews/ratings are:
Walker CalCat Universal Catalytic Converter, 80801
from $142.99
(1)
Walker CalCat Universal Catalytic Converter, 80801
“Had to cut my old Cat and weld new Cat onto ends. Passed my failed 1991 Honda Accord with flying colors. Reduced HC and NOX numbers from the 1000s d”