The catalytic converter is a metal box near the front of the exhaust pipe that filters out harmful gases, such as nitrogen oxide and carbon monoxide. Your exhaust system may have more than 1 catalytic converter. The oxygen sensors are electronic ports that plug into the exhaust system before and after the catalytic converters to check if your engine is burning oxygen efficiently. The wires for the oxygen sensors will go directly into your vehicle’s body. The resonator is a slightly wider section of your exhaust pipe that helps reduce the amount of noise when you run your engine at certain RPMs. Not every exhaust system will have a resonator. The muffler is the large metal box near the rear of your vehicle that helps reduce the amount of noise your exhaust makes. The tailpipe is the small section of tubing that connects to the back of the muffler and allows the fumes to escape into the air.
Don’t touch the exhaust pipes immediately after running your vehicle since they will be extremely hot. You can try spraying the exhaust system with lukewarm water to help cool it down faster.
Avoid using a scissor jack when you raise your vehicle since they aren’t as reliable and they could easily slip. You can also drive your vehicle onto ramps to lift it off of the ground. If you use ramps, be sure to put heavy blocks behind your tires so they’re less likely to roll.
You can buy jack stands from an automotive supply shop. Don’t get underneath your vehicle until you have jack stands firmly in place, or else the vehicle could fall on top of you.
Your vehicle will usually have 1–2 oxygen sensors connected to the exhaust, but it may vary between make and model. Vehicles only have oxygen sensors if they have a catalytic converter. If your vehicle is from 1974 or prior, then the exhaust may not have oxygen sensors. Lie on a rolling creeper trolley to move around under your vehicle more easily. You can buy a creeper trolley from an automotive supply store. Wear clothes that you don’t mind getting dirty as well as disposable gloves so you don’t get too greasy. Make sure you don’t touch the oxygen sensor when the car is hot — or the engine and the exhaust are hot —, since it is attached to the exhaust pipe or to the muffler pipe. Most manufacturers of oxygen sensors now provide anti-seizing or corrosion lubricant that should be applied to the new oxygen sensor when being installed. This is to prevent seizing from occurring.
You can buy penetrating fluid from your local hardware or automotive care store. If you don’t have any penetrating fluid, it may be difficult to remove your exhaust system on your own. If your exhaust system is made up of multiple pieces, then look for bolts where the pieces connect to one another. Spray those with your penetrating fluid as well so you can remove each of the pieces separately.
Use a ratchet with a long handle so you can get more leverage while you’re disconnecting the old exhaust system.
If you have trouble pulling the metal pins off of the rings, try lubricating them with soapy water to help them slide out more easily. Don’t let the exhaust pipe drop since it could be heavy and it may hurt you or damage other components under your vehicle.
Do not drive your vehicle while you have the exhaust system removed since it may be illegal in your area and you will release harmful fumes.
Compare the layout of your old exhaust system to the new one to make sure it can fit. For example, if you have a dual-exhaust engine, then you need a system that has 2 exhaust ports. If your old exhaust system went over your rear axle, then get an exhaust system that comes in multiple pieces so you can easily install it. If you aren’t able to, then you need to see a mechanic to install the system for you.
You can buy a wire cleaning brush from a hardware or automotive care store. If you can’t get the rust off of the bolts, then you may need to replace them so they don’t get stuck later on.
You can buy anti-seize fluid from an auto care or hardware store. You can also apply the anti-seize fluid on the threadings for the oxygen sensors, but don’t let the fluid touch the interior metal sensors, or else they won’t work properly.
You don’t need to use a jack, but the exhaust system may be too heavy to support and secure on your own.
Your new exhaust system should come with a gasket, but you can also buy them from an auto supply shop.
Don’t fully tighten the nuts and bolts yet, or else you won’t be able to move the exhaust system around if you need to reposition it slightly.
Working from the engine toward the back of your vehicle, connect the first exhaust pipe followed by the catalytic converters, the resonator, the muffler, and end with the tailpipe. You may also have extension pipes that connect between some of the pieces. In some cases, you may need to weld the pieces together rather than use clamps, so see what the manufacturer recommends. Systems that come in a single piece won’t use exhaust clamps.
You can also screw in the oxygen sensors before you install the exhaust system if it’s easier to access.
If you have trouble sliding the pins into the hangers, lubricate them with soapy water so they’re easier to move.
If your exhaust system came in pieces, then make sure all of the bolts are tight along the length of the pipe.
Try repositioning the gasket inside the pipe if you still notice a leak. If your vehicle doesn’t have any exhaust leaks, you can remove the jack stands and lower your vehicle with a jack.
