2004 Subaru WRX Emission Control

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    • (0 reviews)
      # mpn984244
      Subaru WRX / WRX STI 2004, Oxygen Sensor by Denso®. Position: Downstream. Denso's light duty oxygen sensor started to appear on vehicles with the development of fuel injection systems. The basic job of the sensor is to monitor the air...
      Corrosion-resistant stainless steel constructionPTFE filter blocks efficiency-robbing contaminants
      $49.52
    • (0 reviews)
      # 485562071
      Subaru WRX 2004, Professional™ Oxygen Sensor by ACDelco®. If your O2 Sensor is not functioning properly, you are robbing yourself of performance and costing yourself money at the gas pump. Let ACDelco’s Professional Oxygen Sensors...
      ACDelco Professional Oxygen Sensors earn the name ACDelco by being put through a variety of tests, often under extreme and unusual conditionsCustomers can receive better gas mileage with a properly working oxygen sensor
      $83.28 - $161.97
    • (0 reviews)
      # 21104193
      Subaru WRX 2004, Air Fuel Ratio Sensor by Denso®. Position: Upstream. Make sure your engine runs efficiently and produces fewer emissions by replacing your malfunctioning fuel-ratio sensors with these top-notch products designed by...
      Designed to help reduce fuel consumption and harmful emissionsMade with the use of state-of-the-art sensor technologies
      $98.12 - $127.77
    • (0 reviews)
      # 73693734
      Subaru WRX STI 2.5L 2004, Oil Catch Can Kit by PERRIN Performance®. The PERRIN Performance Air Oil Separator traps oil from the crank case vents before it enters the intake, thus increasing intercooler efficiency and reduces chances of...
      Increases intercooler efficiencyReduces carbon build up
      $396.00
    • (0 reviews)
      # 35994368
      Subaru WRX 2004, Premium Oxygen Sensor by Bosch®. Position: Downstream. A worn-out oxygen sensor can cause engine performance problems and shorten the life of the catalytic converter. Tune-up your vehicle with an Oxygen Sensor from...
      Up to 15 % savings in fuel costsReduced CO2 emissions
      $51.47 - $66.64
    • (0 reviews)
      # mpn937533
      Subaru WRX / WRX STI 2004, Universal Fit Oxygen Sensor by Bosch®. Position: Downstream. Universal Oxygen Sensors with OE SmartLink are quick and easy to install. Each sensor has enough length of sensor wire to allow maximum replacement...
      Patented SmartLink™ connector systemNo special tools required for installation
      $33.84
    • (0 reviews)
      # 710426092
      Subaru WRX 2004, Wideband Oxygen Sensor by Bosch®. Position: Upstream. This sensor utilizes a sophisticated sensing element enabling it to produce a precise output in proportion to the air/fuel ratio. Wideband sensors use a more...
      Detects the exact amount of unburned fuel in the exhaust streamOE connectors and OE-style harness for continuous wire from connector to sensor
      $118.51 - $168.29
    • (0 reviews)
      # 152247049
      Subaru WRX 2004, Air Fuel Ratio Sensor by NTK®. Position: Upstream. Location: B1S1. Air/Fuel Ratio Sensors Utilize a Sophisticated Sensing Element that Enables Them to Produce a Precise Output in Proportion to the Air/Fuel Ratio. AFR...
      Increases vehicle fuel economy and engine performance while decreasing vehicle exhaust emissionsDirect replacement
      $151.91 - $196.71
    • (0 reviews)
      # mpn2238888
      Subaru WRX / WRX STI 2004, Oxygen Sensor by NTK®. Position: Downstream. Location: B1S2. Thimble type sensors feature a ceramic element that projects into the exhaust system and becomes electrically conductive at high temperature. The...
      Increases vehicle fuel economy and engine performance while decreasing vehicle exhaust emissionsDirect replacement
      $66.10
    • (0 reviews)
      # 81776462
      Subaru WRX 2004, Oxygen Sensor by Delphi®. As one of the leading suppliers of oxygen sensor technology since 1978, Delphi planar technology is the result of their OE and aftermarket engineers partnering together to develop the most...
      OE connectors and wire lengths within 3" of OE specificationsResists high temperatures, vibration damage and wire corrosion to protect signal accuracy, and long life
      $51.65 - $179.36
    • (0 reviews)
      # 689204161
      Subaru WRX / WRX STI 2004, Oxygen Sensor by Spectra Premium®. To ensure your vehicle has optimal performance and fuel economy while producing minimal emissions replace a defective O2 sensor with one backed by the aftermarket’s most...
      Increase vehicle fuel economy and engine performance while decreasing vehicle exhaust emissions100% performance tested to meet vehicle requirements
      $44.65 - $299.01
    • (0 reviews)
      # mpn914970693
      Subaru WRX 2004, Professional™ PCV Valve by ACDelco®. Designed utilizing the latest technology, this product by ACDelco features premium quality and will perform better than advertised. Perfect for your vehicle and lifestyle, it is...
      Designed to deliver trouble-free, consistent performanceRight for your vehicle and lifestyle
      $4.08
    • (0 reviews)
      # 85013469
      Subaru WRX 2004, Small Body Oil Catch Can by Moroso®. This product is made of high-quality materials to serve you for years to come. Designed using state-of-the-art technology and with customers in mind. It will meet your needs and...
      Plumbed into a vehicle's PCV system to capture the excess crankcase vapors, residual oil mist and moisture from reentering the intake tractVehicles from the factory vent these excess crankcase vapors, residual oil mist and moisture right back into the intake manifold which could cause detonation, oil deposits to form in the intake tract including the valves themselves and from lowering the efficiency of the intercooler in intercooler equipped vehicles
      $342.78 - $359.00
    • (0 reviews)
      # mpn1453211679
      Subaru WRX STI 2004, Twin Large Body Oil Catch Can by Moroso®. This product is made of high-quality materials to serve you for years to come. Designed using state-of-the-art technology and with customers in mind. It will meet your needs...
      Plumbed into a vehicle's PCV system to capture the excess crankcase vapors, residual oil mist and moisture from reentering the intake tractVehicles from the factory vent these excess crankcase vapors, residual oil mist and moisture right back into the intake manifold which could cause detonation, oil deposits to form in the intake tract including the valves themselves and from lowering the ficiency of the intercooler in intercooler equipped vehicles
      $362.93
    • (0 reviews)
      # mpn1848278980
      Subaru WRX / WRX STI 2004, Dual Catch Can Kit by Radium®. This product is made of high-quality materials to serve you for years to come. Designed using state-of-the-art technology and with customers in mind. It will meet your needs and...
      High quality at an affordable priceExpertly made from premium materials
      $417.95
    • (0 reviews)
      # mpn1848278981
      Subaru WRX / WRX STI 2004, Oil Catch Can Kit by Radium®. This product is made of high-quality materials to serve you for years to come. Designed using state-of-the-art technology and with customers in mind. It will meet your needs and...
      High quality at an affordable priceExpertly made from premium materials
      $522.45
    • (0 reviews)
      # 211530080
      Subaru WRX 2004, Ultra™ Catalytic Converter by Walker®. Emissions: EPA compliant. Converter Configuration: Universal Fit. Position: Rear. Catalytic Converter Body Shape: Small Oval. With 1 Inlet. Without Air Tube. Without O2 Sensor...
      $70.94
    • (0 reviews)
      # mpn1258167
      Subaru WRX STI 2.5L 2004, ECO II Pre-Cat Catalytic Converter by Eastern®. Emissions: EPA compliant. Converter Configuration: Direct Fit. Position: Front Undercar. Without O2 Sensor Ports. Catalytic Converter Overall Length: 24.5"....
      $238.29
    • (0 reviews)
      # 80149919
      Subaru WRX STI 2.5L 2004, Catalytic Converter and Pipe Assembly by AP Exhaust®. Emissions: EPA compliant. Converter Configuration: Direct Fit. Without Air Tube. The growing concern for the environment means there is a growing need for...
      $228.01 - $296.93
    • (0 reviews)
      # 212123563
      Subaru WRX with Federal Emission 2004, Catalytic Converter by Bosal®. Emissions: EPA compliant. Converter Configuration: Direct Fit. Position: Center. If you’re in need of a replacement catalytic converter, you can’t do better than...
      $302.72
    • (0 reviews)
      # 842158641
      Subaru WRX with Federal Emission 2004, Catalytic Converter and Pipe Assembly by Bosal®. Emissions: EPA compliant. Converter Configuration: Direct Fit. Position: Rear. Catalytic Converter Overall Length: 24". If you’re in need of a...
      $143.96
    • (0 reviews)
      # 86075000
      Subaru WRX / WRX STI 2.0L 2004, Catalytic Converter by DEC®. Converter Configuration: Direct Fit. Pick out a catalytic converter by DEC and get your emissions back into check without worrying to fail again. These catalytic converters...
      $205.63 - $369.85
    • (0 reviews)
      # 842262631
      Subaru WRX / WRX STI 2.0L 2004, Catalytic Converter and Pipe Assembly by DEC®. Converter Configuration: Direct Fit. Position: Rear. Pick out a catalytic converter by DEC and get your emissions back into check without worrying to fail...
      $198.49 - $369.85
    • (0 reviews)
      # 842147628
      Subaru WRX 2004, Catalytic Converter by Davico®. Emissions: EPA compliant. Converter Configuration: Direct Fit. Without O2 Sensor Port. This direct-fit catalytic converter by Davico will be a great solution to replace your failed or...
      $261.35 - $272.94
    • (0 reviews)
      # 198284242
      Subaru WRX 2004, Catalytic Converter and Pipe Assembly by Davico®. Emissions: EPA compliant. Converter Configuration: Direct Fit. With 1 O2 Sensor Port. This direct-fit catalytic converter by Davico will be a great solution to replace...
      $196.59 - $235.92
    • (0 reviews)
      # 380887193
      Subaru WRX STI 2.5L 2004, Heavy Metal Catalytic Converter by MagnaFlow®. Emissions: EPA compliant. Converter Configuration: Direct Fit. Without Air Tube. Catalytic Inlet Diameter: 2.5". Catalytic Outlet Diameter: 2.5". If your car needs...
      $320.31 - $485.43
    • (0 reviews)
      # 317064248
      Subaru WRX 2004, Heavy Metal Catalytic Converter by MagnaFlow®. Emissions: EPA compliant. Converter Configuration: Universal Fit. Without Air Tube. Without O2 Sensor Port. Catalytic Inlet Diameter: 2.5". Catalytic Outlet Diameter: 2.5"....
      $100.27 - $105.95
    • (0 reviews)
      # 317064255
      Subaru WRX / WRX STI 2.0L with LEV Specification / with LEV1 Specification 2004, OBDII Catalytic Converter by MagnaFlow®. Emissions: CARB compliant. Converter Configuration: Universal Fit. Catalytic Converter Body Shape: Oval. Without...
      $179.02 - $185.78
    • (0 reviews)
      # mpn1156305
      Subaru WRX STI 2.5L 2004, OEM Grade Catalytic Converter by MagnaFlow®. Emissions: EPA compliant. Converter Configuration: Direct Fit. Position: Rear. Without Air Tube. Catalytic Inlet Diameter: 2.5". Catalytic Outlet Diameter: 2.5"....
      $398.76
    • (0 reviews)
      # 317064258
      Subaru WRX 2004, OEM Grade Catalytic Converter by MagnaFlow®. Emissions: EPA compliant. Converter Configuration: Universal Fit. Without Air Tube. Without O2 Sensor Port. Catalytic Inlet Diameter: 2.5". Catalytic Outlet Diameter: 2.5"....
      $119.49 - $122.43
    • (0 reviews)
      # mpn1156302
      Subaru WRX / WRX STI 2004, OEM Grade Stainless Steel Exhaust Manifold with Integrated Catalytic Converter by MagnaFlow®. Position: Front. Primary Tubing Diameter: 2.5". Collector Outlet Diameter: 2.5". Emissions: EPA compliant. Color:...
      $583.50
    • (0 reviews)
      # 210570867
      Subaru WRX 2004, Intermotor™ Vapor Canister Purge Solenoid by Standard®. SMP’s vision is to be the leading independent supplier to the automotive aftermarket, providing the highest quality products, competitive prices and the...
      OE quality parts from top original equipment and aftermarket manufacturersThe finest quality at a great price
      $77.37 - $107.77
    • (0 reviews)
      # mpn53663715
      Subaru WRX / WRX STI 2004, Intermotor™ Vapor Canister Vent Solenoid by Standard®. SMP’s vision is to be the leading independent supplier to the automotive aftermarket, providing the highest quality products, competitive prices and...
      OE quality parts from top original equipment and aftermarket manufacturersThe finest quality at a great price
      $51.88
    • (0 reviews)
      # mpn2376929155
      Subaru WRX / WRX STI 2.0L 2004, Vapor Canister Purge Valve by Dorman®. Dorman's Vapor Canister Purge Valve restores on-board diagnosis of the EVAP system. Plus, its high quality metal and plastic construction keeps the system working...
      Designed for enduring resistance to harsh road and weather conditionsDirect replacement for a proper fit every time
      $99.95
    • (0 reviews)
      # mpn2296194
      Subaru WRX / WRX STI 2.0L 2004, Vapor Canister Vent Solenoid by Dorman®. Dorman's Vapor Canister Vent Solenoid is engineered from robust materials to effectively direct the flow of fuel vapor through the EVAP system. Replacement...
      Replacement helps to reduce atmospheric pollution due to hydrocarbon emissionsHigh-quality design for prolonged durability against harsh road and weather conditions
      $46.95
    • (0 reviews)
      # mpn26600538
      Subaru WRX 2004, Lambda Temperature Sensor by Genuine®. Position: Front. This product is made of high-quality materials to serve you for years to come. Designed using state-of-the-art technology and with customers in mind. It will meet...
      High quality at an affordable priceExpertly made from premium materials
      $68.07
    • (0 reviews)
      # mpn1647788215
      Subaru WRX STI 2.5L 2004, Upgraded AOS Fitting Kit by PERRIN Performance®. Designed utilizing the latest technology, this product by PERRIN Performance features premium quality and will perform better than advertised. Perfect for your...
      Designed to deliver trouble-free, consistent performanceRight for your vehicle and lifestyle
      $82.80
    • (0 reviews)
      # mpn520800
      Subaru WRX STI 2.5L 2004, Catalytic Converter Gasket by Victor Reinz®. Position: Center. This product is made of high-quality materials to serve you for years to come. Designed using state-of-the-art technology and with customers in...
      High quality at an affordable priceExpertly made from premium materials
      $15.13
    • (0 reviews)
      # mpn2588217165
      Subaru WRX STI 2.5L Manufactured After April 2004, PCV Valve by MTC®. Is your CHECK ENGINE light on? Has your vehicle failed a state emissions test? Your vehicle's emissions control system is in need of repair, but before you waste your...
      High quality at an affordable priceExpertly made from premium materials
      $14.65
    • (0 reviews)
      # 864275292
      Universal Custom Oil Catch Can by Boomba Racing®. The Boomba Racing Universal Catch Can prevents build up of oil residue in the intake system and the engine. Comes with a bracket that helps to make it easier to mount on your specific...
      Holds over 350ml of liquidInlet/Outlet for 3/8" hose
      +1
      $195.00
    • (0 reviews)
      # mpn4495394025
      Universal Catch Can Quick Drain Valve by Boomba Racing®. Finish: Natural Aluminum. To make draining your Boomba Racing Catch Can even easier! Introducing the Boomba Racing Quick Drain Valve. This piece is meant to replace the 3/16"...
      CNC machined from corrosion resistant stainless steel in-house in Wood Dale, IllinoisUses 1/4" hose for fitting
      $45.00
    • (1 review)
      # 45000611
      Subaru WRX 2004, Oxygen Sensor by Standard®. SMP’s vision is to be the leading independent supplier to the automotive aftermarket, providing the highest quality products, competitive prices and the highest reputation for integrity to...
      One-piece laser welded body for maximum protection and precise operation maintaining sensor integrityDual internal talc seal makes Our Oxygen sensors last longer
      $44.92 - $65.21
    • (0 reviews)
      # mpn1280982071
      Subaru WRX 2004, PCV Valve by Luber-finer®. PCV valves are designed to precisely return crankcase combustion gases to the air intake system. Overextending the part’s service promotes sludge formation, which clogs the engine's interior...
      Return crankcase combustion gases to the air intake systemDesigned to deliver optimum performance
      $3.79
    • (0 reviews)
      # mpn457852240
      Subaru WRX STI 2.0L 2004, Breather Oil Catch Tank Kit by AVO®. To keep your engine cool and improve your vehicle's performance, this product is just the right solution. Manufactured from high-quality materials, it will surely provide...
      Made to keep your engine running coolImproves your vehicle's performance
      $190.00
    • (0 reviews)
      # mpn1231686
      Subaru WRX STI 2.5L 2004, ECO II Catalytic Converter by Eastern®. Emissions: EPA compliant. Converter Configuration: Universal Fit. Position: Front Undercar. Catalytic Converter Body Shape: Round. Without O2 Sensor Ports. Catalytic...
      $46.10
    • (0 reviews)
      # mpn1275099
      Subaru WRX STI 2.5L 2004, Standard Catalytic Converter and Pipe Assembly by Eastern®. Emissions: EPA compliant. Converter Configuration: Direct Fit. Position: Rear. Location: Undercar. With 1 O2 Sensor Port. Catalytic Converter Overall...
      $203.87
    • (0 reviews)
      # 172053797
      Subaru WRX 2004, Catalytic Converter by Eastern®. Converter Configuration: Universal Fit. Catalytic Converter Body Shape: Oval. Whether your catalytic converter is damaged by road debris or failed due to an engine problem, you...
      $38.35 - $80.65


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