So Fix it

A catalytic converter is an exhaust component that was put on all production cars since 1974. The job of a catalytic converter on a Pontiac Grand Prix is to burn up any left over gas that went through the engine and was left unburned. The catalytic converter uses a chemical reaction to change the unburned engine gases to less toxic gases, like carbon dioxide and water vapor. This helps cut down on the pollutants emitted, from the Grand Prix, into the atmosphere.

General Location

Because the catalytic converter is an exhaust component, it is located in the exhaust system on the underside of the Grand Prix. On the Grand Prix, the exhaust system attaches to the engine block and to the underside of the car using brackets, and then exists out the rear of the vehicle with dual exhaust tips. The converter looks like a small muffler, or rectangular box, around the middle of the exhaust pipe. The primary components of the converter are usually made out of stainless steel.

Location on the Exhaust

The catalytic converter is located between the exhaust manifold and the muffler. The exhaust manifold is a pipe that moves the engine gasses from the engines combustion chamber into the exhaust system. The muffler is a large chamber located near the end of your exhaust system that reduces the noise energy of the exhaust gasses as they exit the exhaust system.

Why Its on the Car

Toxic gasses are released when the engine in the Grand Prix runs. These gasses could cause depletion of the ozone, as well as illness or damage to the environment, if they were released without being broken down into less harmful gasses. Because the government put emission restrictions into place to slow the buildup of pollution, all cars were equipped with catalytic converters after 1974. This has cut down on the pollution being released by automobiles significantly since the government required all cars to have the converter.

Why Its in the Exhaust System

The exhaust system on the Grand Prix, just like every other car, is used to move gas from the engine out to the surrounding air. The converter is located after the exhaust manifold so that it can take the toxic engine gasses and convert them into less toxic ones before the exhaust moves into the muffler and eventually exist the rear of the Grand Prix. Without the catalytic converter within the exhaust system, exhausted toxic gases from the engine would be released into the atmosphere, causing toxic buildup.

Cat-back (a.k.a. "catalytic converter back") exhaust systems are a popular add-on for enthusiasts seeking an increase in horsepower, fuel economy and torque. Additionally, these systems can add personality to any car by making the exhaust note deeper, louder and overall more aggressive. The fact that cat-back exhaust systems do not affect emissions in any way has made them a universally accepted mod in every state in the union.

Definition

An exhaust system has between five and eight basic parts, depending on the car. The system starts at the exhaust manifold(s) or header(s), which combine the exhaust output of the individual cylinders into one port (called a "collector"). The collector can connect to a mid-pipe (which links the manifold and converter) or can feed directly into the converter itself. Everything after that is the cat-back portion, which includes the crossover (on dual-exhaust, V-configured engines), the main tube section and the muffler(s). Some exhaust systems use one or more small intermediary mufflers (called "resonators") in the main pipe to deepen and smooth the exhaust note.

Power Benefits

When it comes to the cat-back, most original equipment manufacturers (OEMs) put far more emphasis on noise level and production cost than engine note and performance. The original pipes (especially on older cars) are often too small to allow exhaust to flow as freely as it could, and stock mufflers can be a significant impediment to exhaust flow. Almost any cat-back system will enhance power, torque over a stock system. These benefits can range from 1 to 2 horsepower on four cylinders to 30 to 40 on large engines with restrictive exhausts.

Fuel Economy

With all the emphasis manufacturers place on fuel economy, it might seem surprising that they dont just install larger exhaust systems in the first place. Cat-back systems help the engine to run more efficiently, which is always good for at least a small boost in fuel economy. Turbodiesel engines generally stand to gain the most; 10 percent improvements in fuel efficiency are not unheard of when used with a freer-flowing air filter.

Design

Aftermarket cat-back systems are generally made of large and free-flowing "mandrel bent" tubing, which doesnt have the flow-inhibiting kinks that most stock systems do. Many dual exhaust systems incorporate an X-pipe crossover to balance exhaust flow for increased horsepower and a smoother-sounding exhaust note. You have a choice of higher flowing fiberglass or steel-packed mufflers (such as those that originally came in the car) or "chambered" mufflers that often yield a quieter and lower exhaust note.

Sound

Although you might be tempted to buy the thinnest and lightest exhaust system on the market, youll probably regret it. Engines (particularly small ones) produce a whole spectrum of high-frequency sound, which vibrates the system and causes it to act like a giant speaker. This "drone" sounds bad and is certain to drive you insane with migraines. Thicker, larger diameter pipes will contain the exhausts high frequency sound and promote propagation of more pleasing low-frequency soundwaves.

A catalytic converter is used to convert potentially harmful emissions into gases that are not dangerous. Since it is a relatively recent car part, many people are unfamiliar with what it does and how it is used. It is important to be familiar with the workings of a car before you work on one, since a catalytic converter is a very expensive car part.

Instructions

1

Use a jack to raise the car up. Place two jacks on the front and two on the back. Ensure the car is stabilized by using jack stands with the jack support points.

2

Lubricate both the bolts and clamps so they will be easier to remove. Loosen the bolts with an adjustable wrench, since bolt sizes vary. Remove the bolts and put them somewhere safe.

3

Remove the heat shield and clamps. Shake the catalytic converter slightly and pull it from the pipes. In some occurrences, you may need to use a rubber mallet and tap on the converter to release it.

4

Check the connecting pipes for damage. If you see damage, you might need to replace the pipes, while a small crack or puncture can be replaced with an exhaust patch kit you can purchase at an automotive store.

5

Attach the new converter to the exhaust pipe that comes from the front of the vehicle. You may need to use the rubber mallet to ensure that the converter is securely fastened. Align the exhaust pipe from the vehicles rear with the catalytic converters back hole. It may require pushing the pipe back to get it fixed. When it is properly aligned, push the pipe one inch into the converter.

6

Put the heat plate back on, if you removed one, then replace and secure the bolts. Come out from under the car then start the engine. See if the new converter is leaking. Most leaks occur where the exhaust pipes meet the converter. Should you see a leak, you will need to use the automotive exhaust patch kit to patch it up.

7

Remove the jack stands and lower the vehicle. Write the date of the replacement in your auto maintenance manual. Some states, like California, require this information with auto inspections.

8

Check to see your states requirements for disposing of catalytic converters. Some states require you to take it to an approved location for disposal. You can find this by contacting a local auto store or mechanic.

The "cat converter," another name for a catalytic converter, is a part of a vehicle designed to reduce emissions. Car makers have been required to install the devices, containing valuable palladium and platinum, in new cars since 1975, though in recent years car makers have been finding ways to make them without valuable metals. Still, because of the metals inside many converters, scrap metal recyclers will accept them for recycling.

Instructions

1

Search to find the best price for your cat converter. In 2010, platinum is worth about $1,700 an ounce. Youre not likely to get even close to that for the amount of platinum inside your cat converter, but its good to know how much platinum is worth. Look for a model number on your cat converter and search classified ads to find what that type of cat converter is selling for. Use this research as a guide when you go to recycle your converter.

2

Find a scrap metal recycler near you. Many cities have at least a few scrap metal recyclers that you can find under "scrap metal" in business listings. Also check with the local garbage hauler to find out which places they recommend, or search the database of Earth911 under "scrap metal." Once youve found a place to accept your cat converter, note their hours and location.

3

Take your cat converter to the scrap metal recycling center of your choice. Bring your identification, as many states have laws that track metal recycling to cut down on theft.