How to Replace a Catalytic Converter on Vehicles

by Contributing Writer

When most people think of exhaust systems on their Vehicles they think of mufflers, but an important component that comes before the muffler is the catalytic converter. The catalytic converter cleans the emissions and pollutants that are produced from the combustion engine. The catalytic converter is like a filter that captures carbon molecules. Replacing a Vehicles catalytic converter may be necessary if your car is driving sluggishly and there are increased emissions coming out of your muffler. Mechanics can perform an emissions test on your Vehicles exhaust to make sure it is your catalytic converter that is the problem. Replacing a Vehicles catalytic converter is easy to do in your own driveway.

Under The Hood:

 How to Replace a Catalytic Converter on a KIA Sedona

Place the Sedona on a car lift and bring the vehicle all the way up on the lift.

Put on the cutting glasses and light the oxyacetylene torch. Cut the two bolts on the front converter flange with the torch. Cut the bolts flush to the flange on the converter side.

Cut the two bolts on the rear converter flange in the same manner.

Shut off the torch and switch the cutting glasses to safety glasses. Put on the safety gloves.

Knock out the remainder of the bolts on the front flange connection using the hammer and a long-stemmed punch. Knock out the remainder of the bolts on the rear converter flange. Allow the converter to cool down.

Remove the catalytic converter hangers from the rubber exhaust hangers and remove the converter.

Clean the flange connections of the front pipe and the front muffler that the converter attaches to using the angled die grinder and a coarse reconditioning disc.

Install the new converter and gaskets. Place the converter hanger into the rubber exhaust hangers first to hold it up, insert the gaskets between the flanges and place the bolts through the flange holes to support the converter. Use a flat washer against the bolt head on one side and the lock washer and nut on the other side.

Tighten the bolts and nuts with the impact gun, swivel and a socket while holding the bolt heads with a hand wrench.

Remove the debris below the Sedona and lower it down to the floor.

Start up the engine and relift the Sedona to check for exhaust leaks at the front or rear flange connections.

Items you will need

  • Car lift

  • Oxyacetylene torch

  • Safety glasses

  • Cutting glasses

  • Safety gloves

  • Hammer

  • Long-stemmed punch

  • Direct-fit catalytic converter replacement with gaskets (2)

  • 4 each bolts, flat washers, lock washers and nuts

  • Pneumatic angled die grinder

  • 2-inch coarse reconditioning discs for the die grinder

  • 3/8-inch drive pneumatic impact gun

  • 3/8-inch drive impact socket set

  • 3/8-inch drive impact universal swivel

  • Hand wrench set

 How to Replace the Catalytic Converter in a 2002 Chevy Avalanche

Take the negative (-) cable off the battery with a wrench. Use the jack to jack up the truck. Place the vehicle on on jack stands.

Disconnect the y-pipe at the exhaust manifolds by removing the mounting nuts on both right and left exhaust manifolds. Use a socket and ratchet with a long extension for this task.

Unplug the electrical plugs on the right and left oxygen sensors. The oxygen sensors are located in the y-pipe, which is in front of the catalytic converters. Use a socket and ratchet to take off the two bolts and nuts connecting the y-pipe to the exhaust pipe. Take the gaskets out and remove the y-pipe with the catalytic converters in it from the vehicle. Remove both oxygen sensors from the old y-pipe.

Put both oxygen sensors into the new y-pipe with a socket specially made for oxygen sensors. Take a wire brush and clean the exhaust manifold where the gasket seats to the manifolds. Put the y-pipe up to the exhaust manifolds with the inner nut on each side. Hold the y-pipe up and place the gasket between the y-pipe and the exhaust pipe; replace both nuts and bolts making sure the bolts go through the gasket.

Place the two gaskets in the pipe that attaches to the exhaust manifolds and replace the other two nuts. Make sure the gaskets are seated straight on both exhaust manifolds and tighten all four nuts.

Jack up the vehicle, remove jack stands and lower the vehicle. Clean the battery post and connect the negative cable to the battery.

Items you will need

  • Wrench set

  • Jack

  • Jack stands

  • Socket and ratchet set

  • Wire brush

  • New y-pipe with bulletin converters

 How to Replace a Catalytic Converter on a Toyota Corolla

Go to your local auto store. Buy the proper model of catalytic converter for your Toyota Corolla.

Slide under the Toyota Corolla. Find the catalytic converter. It is 3 to 4 feet behind the muffler and approximately 1 foot behind the engine.

Unscrew the four bolts holding the front of the catalytic converter to the exhaust pipe coming from the engine. Unscrew the four bolts holding the back of the catalytic converter to the exhaust pipe going to the muffler.

Place the new catalytic converter in place of the old one. It will only line up with the bolt holes in the correct direction. Screw the four bolts into the front and the back of the catalytic converter.

Items you will need

  • Wrench set

  • Catalytic converter

  • Safety glasses

 How to Replace a Catalytic Converter in a Honda

Removing the Catalytic Converter

Raise the vehicle according to instructions listed in the owner's manual and support with jack stands.

Spray the retaining bolts with a penetrating oil such as WD-40. There are five bolts that connect the catalytic converter to the exhaust pipes: two in the front and three in the back.

Remove the bolts that connect the front of the catalytic converter to the head pipe.

Remove the bolts that connect the rear of the catalytic converter to the exhaust pipe.

Remove the catalytic converter from the vehicle.

Installing a Catalytic Converter

Coat the threads of the retaining bolts with an anti-seize compound.

Raise the catalytic converter into position between the head pipe and exhaust.

Install the bolts that connect the rear of the catalytic converter to the exhaust pipe, but do not tighten.

Install the bolts that connect the front of the catalytic converter to the head pipe.

Tighten the bolts.

Lower the vehicle.

Items you will need

  • Jack stands

  • Metric wrench set

  • Metric socket set

  • Penetrating oil (WD-40)

  • Anti-seize compound

 How to Replace the Catalytic Converter on a Trailblazer

Raise the front of your Trailblazer with a jack and support it on a set of jack stands positioned under the frame rails. Slide under the passenger's side of the vehicle and locate the catalytic converter in the exhaust pipe between the engine and the muffler.

Locate the oxygen sensor in the converter. Follow the wire from the sensor to the wire harness connector and disconnect it from the harness. Place an oxygen-sensor socket on the sensor and remove it from the converter with a ratchet. Set it aside.

Loosen the two bolts on the mounting flange between the rear of the catalytic converter and the exhaust pipe using a socket and ratchet. Remove the bolts from the flange and pull the pipe aaway from the converter. Push the pipe aside.

Move to the front of the converter and remove the two mounting bolts between the flange and the front pipe with a wrench. Pull the converter out and remove it from under the truck.

Position a new converter in place under the truck. Lift the converter up into place and install the retaining bolts from the front pipe to the front flange on the converter. Leave them loose for now.

Position the rear pipe up against the rear flange and install the rear mounting bolts loosely. Tighten the front bolts by torquing them to 33 ft.-lbs., then tighten the rear bolts to 33 ft.-lbs. as well.

Install the oxygen sensor from the old converter into the new converter and tighten it with a oxygen sensor socket and ratchet. Connect the wiring harness connector from the oxygen sensor to the wiring harness connector on the truck. Push the connectors together until they lock in place.

Raise the front of the truck off the jack stands with a jack. Remove the stands from under the truck, lower the jack and remove it from under the truck.

Items you will need

  • Jack

  • Jack stands

  • Oxygen-sensor socket

  • Ratchet

  • Socket set

  • Torque wrench

 How to Replace the Catalytic Converter on a Pontiac Vibe

Raise the Vibe's rear end with a floor jack and support it on jack stands. The catalytic converter looks similar to the muffler, but is located closer to the engine.

Apply penetrating oil to the nuts and studs connecting the converter to the exhaust manifold.

Unscrew and remove the nuts on the front exhaust flange with your wrench and separate the front end from the exhaust manifold.

Dress in long-sleeved, flame retardant clothing, along with a full protective welder's mask, and cut the rear end of the catalytic converter from the Vibe's exhaust pipe using an acetylene cutting torch.

Install the replacement converter to the exhaust flange using the nuts and your wrench.

Weld the catalytic converter onto the rear exhaust pipe with your welding torch.

Lower the car off the jack stands once the weld is cool and solid.

Items you will need

  • Floor jack

  • Jack stands

  • Welding/cutting torch

  • Penetrating oil

  • Wrench

  • Leather gloves

  • Long-sleeved clothing

  • Welder's mask

 How to Replace the Catalytic Converter on a Jeep Cherokee

Locate the catalytic converter. Lie on your back and slide under your Jeep Cherokee. The catalytic converter is connected into the exhaust system pipe. It is bolted to the exhaust pipe coming from the engine, and the back of the catalytic converter is bolted to the exhaust pipe running to the muffler.

Place the proper socket size on the nuts holding the U-bolts through the catalytic converter brackets. Unscrew the two bolts in the front and back of the catalytic converter.

Place the new catalytic converter between the exhaust pipes. There will be an arrow on the base of the catalytic converter; the arrow should be point toward the engine.

Tighten the nuts back on the bolts that go through the brackets on the front and back of the catalytic converter.

Items you will need

  • Catalytic converter

  • Socket wrench set

  • Safety goggles

 How to Replace a Catalytic Converter With a Straight Pipe

Park the vehicle on a level surface and raise it with a hydraulic jack. Place jack stands under each corner of the vehicle's frame. Lower the hydraulic jack until the vehicle is fully supported by the jack stands.

Allow the exhaust system to cool if the vehicle has been driven recently, as the catalytic converter can be extremely hot.

Crawl under the vehicle and spray penetrating fluid onto the catalytic converter mounting bolts. Allow the fluid to work in for at least fifteen minutes.

Loosen the mounting bolts on each end of the catalytic converter with an adjustable wrench in a counterclockwise direction. Remove the bolts and place them aside. Lower the catalytic converter carefully to the ground. Retain the catalytic converter for possible installation in the future.

Place a test pipe (available at auto parts stores) into the exhaust system in the void left by the catalytic converter. Twist the pipe around by hand until the mounting holes in the flanges on the test pipe and the adjoining exhaust pipes line up.

Place the original mounting bolts into the holes in the flanges and tighten with an adjustable wrench in a clockwise direction.

Raise the vehicle with the hydraulic jack and remove the jack stands. Lower the hydraulic jack until vehicle is resting on the ground. Remove the hydraulic jack.

Items you will need

  • Hydraulic jack

  • (4) Jack stands

  • Penetrating fluid

  • Adjustable wrench

  • Test pipe

 How to Replace a Catalytic Converter On a Ford Escape

Be sure the vehicle is cold and slide under the passenger side. Bring along the wire coat hanger, socket set, box wrenches and replacement catalytic converter.

Wrap the coat hanger around the exhaust pipe behind the catalytic converter and up through the frame to keep the pipe suspended.

Use the socket set and box wrenches to unbolt the fasteners in the front and rear flanges of the existing catalytic converter. Set the fasteners aside and put the old catalytic converter on the ground, out of the way.

Position the new catalytic converter between the collector pipe and exhaust pipe and reinstall the bolts into the front and rear flanges with the socket set and wrenches.

Remove the coat hanger from the frame and exhaust pipe and slide out.

Items you will need

  • Wire coat hanger

  • Socket set

  • Box wrenches

  • Replacement catalytic converter