Depending on how the catalytic converter is mounted to your vehicle, you could swap it out yourself.
It’s going to be bolted or welded on the exhaust, according to Scotty Kilmer. If you have a welder, you can still do it yourself, though most people do not have this equipment.
How do I know when my catalytic converter is bad?
Some of the symptoms of a bad catalytic converter include:
- A rough-running engine
- Gas mileage takes a hit
- Stinky exhaust
- The check engine light comes on
If you believe one or more of the catalytic converters on your vehicle are bad, check to see how they are attached. Those that are bolted up are much easier to replace. To learn more about replacing your vehicle’s catalytic converter, please continue reading.
What a Catalytic Converter Does and Why My Vehicle Needs it
Because of the expense of a catalytic converter, many people would rather take it right out of the exhaust system and replace it with another piece of exhaust. However, the catalytic converter is one of the most important parts of the exhaust system.
The catalytic converter helps to keep your vehicle’s hydrocarbon emissions within acceptable levels. While it’s made to last the life of a vehicle, that doesn’t always happen. The catalyst inside breaks down over time, or it rusts out from being exposed to the elements.
If your vehicle’s engine is not running properly, the excessive fumes going through the catalytic converter break the catalyst down faster than the manufacturer planned. Because the catalytic converter is sealed, you must replace it – you cannot repair it.
Removing and Replacing the Catalytic Converter
Step 1: Locate the jack points for your vehicle. With a hydraulic jack, jack the vehicle up, then place four jack stands under the vehicle. Make sure you jack it up high enough so that you can work under it.
Step 2: Set wheel chocks behind the wheels so that the vehicle doesn’t roll off the jack stands. Set the parking brake.
Step 3: Determine whether your vehicle’s catalytic converter is bolted on or welded on. If it is welded, you’ll need a welder or will need to take it to a muffler shop. The catalytic converter is usually closer to the front of the vehicle.
Single exhaust vehicles will have one or two catalytic converters, while dual exhaust vehicles will have two or four catalytic converters.
Step 4: Locate the oxygen sensors. If an oxygen sensor is close to or mounted on a catalytic converter, unplug it, then remove it. You will need a special socket made for oxygen sensors or an open-end box wrench.
Step 5: If the catalytic converter is bolted on, spray the nuts on the exhaust flange with penetrating oil and allow them to soak for a few minutes. If they still don’t loosen, spray them again. You want to try to not break the bolts when they come out.
Step 6: Support the converter with a jack or blocks of wood so it doesn’t fall on you when you remove the bolts. Remove all of the bolts in the exhaust flanges behind and in front of the catalytic converter.
Step 7: Install the new catalytic converter. Use new gaskets between the converter and the flanges, unless you have metal gaskets that are made to reuse.
Step 8: Jack the vehicle up off the jack stands. Remove the jack stand, then lower the vehicle to the ground. Remove the wheel chocks. Start the vehicle and listen for exhaust leaks.
Welding a Catalytic Converter
The steps for welding a catalytic converter are nearly the same as removing a bolt-on converter. Before welding:
Make sure covers, wiring, cables, intake pipes and other obstructions are out of the way, especially those that will burn or melt.
Support the catalytic converter so it doesn’t drop down and smack you in the head.
Cut the exhaust near the catalytic converter in the front and rear with an oxy-acetylene torch.
Use a MIG or TIG welder to weld exhaust systems. Most people recommend using a MIG welder since exhaust pipes are made of relatively thin metals.
If you can’t get a good bead because of inexperience, let someone experienced weld the catalytic converter. Having an exhaust leak is not only annoying, but it could damage other components of the exhaust system, including the oxygen sensor and EGR valve.
Always use a welding helmet when welding.
Visit Vehicle History
Before you purchase a vehicle, know what you are spending your hard-earned money on. Reading vehicle reviews before you visit the dealer can help you make a better decision.
To learn more about vehicle maintenance and repair, and to read customer comments and professional reviews on various makes and models, visit Vehicle History.
