How to Install a Subaru Catalytic Converter
Toxic emissions, low fuel economy, poor engine performance, and bad exhaust-this is what a faulty catalytic converter can do. If the device can't effectively transform toxic compounds such as hydrocarbon, carbon monoxide, and nitrogen oxide into less harmful substances, the bad catalytic converter can ruin your driving experience and the vehicle can fail the emissions test. Install a new Subaru catalytic converter. Here's how:
Required skill level: Intermediate to Expert
Needed tools and materials
- New catalytic converter
- Jack and jack stands/Hydraulic lift
- Penetrating oil
- Sawzall (for a welded-in catalytic converter)
- Welding machine (for a welded-in catalytic converter)
Preparing for the job
Lift the vehicle off the ground, not just one corner. Raise it with a jack and support it with stands or use a hydraulic lift. The vehicle has to be parked on a level surface. Don't start any work on the catalytic converter until you're sure that the vehicle's exhaust has cooled down. You have to slide underneath the vehicle to trace the lines of the exhaust and locate the catalytic converter (use the vehicle manual as a guide if you have to). See if the device is bolted or welded to the rest of the exhaust system. If it's welded, you need a sawzall or a similar tool and a welding machine in order to replace it. If you don't have access to these tools and don't have the advanced skills to handle these, it would be best to leave the job to a certified mechanic.
Removing the old catalytic converter
Pull out the oxygen sensor from the catalytic converter. Some catalytic converters are even equipped with more than one oxygen sensor. Use an oxygen sensor socket and ratchet wrench to remove it.
For the bolt-in catalytic converter
Apply some penetrating oil to the bolts to make it easier to undo them. Leave this on for several minutes before you loosen the bolts using a right-sized wrench. Start at the back end first and then at the front. Remove the rear bolts first before those on the front. Once all the bolts are removed, you can now detach the converter. Support the exhaust once the converter has been pulled out.
For the welded-in catalytic converter
Cut the converter out of the pipes where it's connected with a sawzall or a similar tool. The cut should be along or near the weld lines. If the converter can't be moved easily, you'll need a little help with the hammer to take this out its place. However, be careful not ruin any part with just a gentle strike or blow.
Installing the new catalytic converter
Note: Check the installation instructions or guide on the new catalytic converter. Installation or the steps for replacement will vary depending on the catalytic converter.
For the bolt-in catalytic converter
Slide in the gaskets that come with the new converter. Bolt-in converters may come with gaskets that sit within the pipes that are connected to the converter. Install these gaskets according to manufacturer instructions.
Set the new converter in place. Line it up and hold it in proper position. Make sure that this is in the right direction and it's facing the right side. Once properly placed, tighten down the bolts with a right-sized wrench. Start at the front and then at the back.
For the welded-in catalytic converter
Weld the converter using a welding machine (MIG welder, e.g.). Welding should be done by a skilled or trained welder. As you weld the device, the converter must be connected to the exhaust system pipes at both ends. Each weld should create an air-tight seal. Let each weld to cool properly.
After installing the converter, you can re-attach the oxygen sensor. Screw it back into place. See to it that the wiring is well and intact.
Testing the newly installed catalytic converter
Double-check the attachment to ensure that it's properly installed and connected. The bolts should be tight and there should be no leaks from the exhaust. Test it out. See how the vehicle runs.
Subaru Catalytic Converter Buyer's Guide
- A catalytic converter, or a cat con, reduces air pollutants and toxic gases in the exhaust gas and breaks them down into less toxic compounds by using catalysts in the form of platinum or palladium.
- If you have a bad cat con, you’ll notice that your engine is performing poorly and doesn’t accelerate well. You’ll also notice that your vehicle will emit a dark exhaust smoke and a rotten egg smell. The underside of the car may also heat up.
- Consider the type and fit of the replacement cat con you’re going to buy. Also, make sure that it is compliant with the legislation in your state.
- The price of an OE replacement Subaru catalytic converter ranges from $40 to $1200.
Subaru as a company is driven by its principles of equity, diversity, and inclusion and wholly devotes its energy into making vehicles that last a lifetime. If your Subaru catalytic converter shows signs of breaking down, you’ll want a high-quality replacement part. This short guide will help you see the symptoms of a failing Subaru catalytic converter and give you some tips before buying a replacement part.
What is a catalytic converter and how does it work?
A catalytic converter, or a cat con, reduces air pollutants and toxic gases in the exhaust gas and breaks them down into less toxic compounds. The catalytic converter uses a catalyst in the form of platinum or palladium to coat the insides of a ceramic honeycomb structure. The ceramic structure is housed inside a muffler-like casing and is attached to the exhaust pipe of the vehicle.
There are two types of cat cons: two-way and three-way. Two-way cat cons are used in diesel-powered engines while three-way cat cons are more common and are used in gas-powered engines. In two-way cat cons, the catalyst converts carbon monoxide into carbon dioxide and breaks down hydrocarbons into carbon dioxide, and water. A three-way cat con does the same thing but it can break down nitrogen oxides back into nitrogen and oxygen as well.
Bad catalytic converter symptoms and their causes
Subarus usually have multiple cat cons that come in Y-pipe assemblies and are bolted onto both sides of the engine. Some newer models might even have a third or fourth cat con installed. Cat cons are susceptible to damage because of their location, structure, and types of substances that pass through them.
You’ll know that you’ll need a catalytic converter replacement if you notice more than one of the following symptoms:
- Reduced engine performance and acceleration
- Dark exhaust smoke
- Excessive heat under the vehicle
- The smell of sulfur/rotten eggs coming from the exhaust.
How to buy a Subaru catalytic converter
Before buying a catalytic converter for your Subaru, you’ll need to consider a few things first. Below are some things you have to keep in mind as you’re buying a replacement Subaru catalytic converter:
Two-way cat cons are usually used in diesel engines while three-way cat cons are used in gas-powered engines. Make sure you’re getting the right cat con type for your Subaru before buying a replacement part.
Replacement cat cons come in universal and direct fit. With direct-fitting catalytic converters, you won’t have to make alterations as they’re usually bolt-on parts. On the other hand, universal cat cons may need modifications and welding which might take up more time to install.
In January of 2009, the California Air Resources Board (CARB) passed a stricter regulation on the sale of aftermarket cat cons in California. In 2014, New York followed suit. If you’re from these two states, you’ll need to purchase a California emissions catalytic converter. Otherwise, you’re eligible to buy a federal emissions cat con.
How much is an OE replacement Subaru catalytic converter?
The price of an OE replacement Subaru catalytic converter ranges from $40 to $1200 and depends on several factors including the year and model of your Subaru.
You can browse for OE replacement Subaru cat cons at CarParts.com. Using the vehicle selector tool on the website, you can narrow down your choices to your Subaru’s specific year and model. You can also use the advanced search filter tool to indicate your preferences on brand, fit, location, and emissions regulation type. A Subaru catalytic converter replacement is typically sold individually, in sets of 2, or as an assembly.