The Exhaust System
Your car's exhaust system carries away the gases created when
the fuel and air are burned in the combustion chamber. These
gases are harmful to humans and our environment. A frequent
check of your exhaust system is a must to provide for you and
your family's safety. Make sure there are no holes in the
exhaust system or in the passenger compartment where exhaust
fumes could enter. Let's begin by listing the parts of the
exhaust system and their functions. Exhaust manifold: The
exhaust manifold attaches to the cylinder head and takes each
cylinders exhaust and combines it into one pipe. The manifold
can be made of steel, aluminum, stainless steel, or more
commonly cast iron. Oxygen sensor: All modern fuel injected cars
utilize an oxygen sensor to measure how much oxygen is present
in the exhaust. From this the computer can add or subtract fuel
to obtain the correct mixture for maximum fuel economy. The
oxygen sensor is mounted in the exhaust manifold or close to it
in the exhaust pipe. Catalytic converter: This muffler like part
converts harmful carbon monoxide and hydrocarbons to water vapor
and carbon dioxide. Some converters also reduce harmful nitrogen
oxides. The converter is mounted between the exhaust manifold
and the muffler. Muffler: The muffler serves to quiet the
exhaust down to acceptable levels. Remember that the combustion
process is a series of explosions that create allot of noise.
Most mufflers use baffles to bounce the exhaust around
dissipating the energy and quieting the noise. Some mufflers
also use fiberglass packing, which absorbs the sound energy as
the gases flow through. Exhaust pipe: Between all of the above
mention parts is the exhaust pipe which carries the gas through
it's journey out your tail pipe. Exhaust tubing is usually made
of steel but can be stainless steel (which lasts longer due to
it's corrosion resistance) or aluminized steel tubing.
Aluminized steel has better corrosion resistance than plain
steel but not better than stainless steel. It is however cheaper
than stainless steel. Common Problems: Well the worst enemy of
your exhaust system is corrosion.... or more commonly known as
rust. Rust is caused by moisture reacting with the iron in the
steel and forming iron oxide. Moisture, or water vapor is
present in the exhaust as a by-product of combustion and the
catalytic converter. Moisture can also come from the outside in
the form of rain. Short trips in your car can shorten the life
of your exhaust system. When you shut down your engine whatever
water vapor is in the pipes condenses and turns back into a
liquid. On a short trip the water never has a chance to get hot
enough to turn back into water vapor and just stays in the
system and rusts away the pipes. If you drive for short
distances consider replacing your exhaust system with stainless
steel when the plain steel one rusts through. If you drive more
than 15 miles at a time then you should not have to worry about
this. If you live in an area, which uses salt on the roads in
the wintertime, make sure to wash the underside of you car with
water every few weeks. Salt speeds up the corrosion process and
getting it off as soon as possible will help stop the corrosion.
Make sure you run the engine after washing to drive off all of
the water on the pipes. Noticing a decrease in your gas mileage?
Your oxygen sensor could be going south on you. As time goes on
the oxygen sensor begins to wear out and becomes less accurate.
This sometimes results in a rich fuel mixture where your engine
burns more fuel than is needed. Most of the time your check
engine light will come on and alert you to a failing oxygen
sensor. I suggest changing the oxygen sensor every 60,000 miles
just to be safe. Even though your check engine light might not
be on, you could be using more gas than is needed. Pay a few
bucks and change the sensor, your wallet will thank you when you
have to buy less gas down the road. The next part in line to go
is the muffler. Most of the time mufflers rust through and need
to be replaced. There are allot of options out there for
replacement mufflers. Some cheap and some expensive. It holds
true... you get what you pay for. If you plan on keeping your
car for any period of time, spend the extra cash and get an OEM
muffler or a high quality name brand muffler. On rare occasions
the catalytic converter will become clogged and need to be
replaced. Symptoms include loss of power, heat coming from the
floor of your car, glowing red converter or a sulfur smell.
Never let a mechanic tell you that you can do without the
catalytic converter. Removing this component is illegal in most
states and can lead to a hefty fine to the government if you are
not careful. That's about it for the exhaust system; just
remember that rust is the biggest enemy to your exhaust system.
Take the above-mentioned steps and your exhaust system will last
a long time