The fuel system pumps fuel into the cylinders of the internal combustion engine
and mixes it with the perfect amount of air for combustion. There are
two types of fuel systems:
Carburetors.
Prior to 1985, most vehicles used a carburetor. A carburetor uses a
venturi (narrowed passage within the carburetor) to draw fuel from a
float bowl based strictly on the volume of air flowing through the
carburetor. A carburetor is a primitive method of mixing air and fuel.
it is far less efficient than modern fuel injection. That’s why all
modern cars today are built with fuel injection.
Fuel injection
Fuel injection is a complex electrical circuit using multiple sensors
as inputs to a PCM (powertrain control module, also called the
computer). The PCM then interprets the inputs from these sensors and
produces a PWM (pulse width modulated) signal. A PWM signal is a digital on/off signal. This translates into how much fuel is injected
into the engine.
The PCM then receives feedback signals from oxygen sensors. An oxygen
sensor is a sensor that checks the air-fuel ratio by monitoring exhaust
gas at or near the exhaust
manifolds. Using this information, the PCM
can adjust fuel trim accordingly to keep the engine running clean, long, and efficiently. This is one of the main reasons newer automobiles last
so much longer, burn less fuel, and have cleaner emissions.
Fuel Filter and Air Filter:
The fuel system is very sensitive to contamination and debris. A small amount of contamination can cause severe problems in any fuel system. Therefore, these filters are critical for protecting the fuel system and engine. There are two filters that protect the fuel system and engine
the
fuel filter
When you fill your vehicle with fuel from a gas station, the fuel will have
contaminants. Between the fuel tank and the engine, the fuel passes through
a sock filter which prevents large contaminants from passing through. Then
the fuel will pass through the fuel filter which prevents small
contaminants from passing. Anything that passes through the fuel filter can
pass through the rest of the fuel system.
the air filter.
An air filter protects the engine from dust and dirt entering the
combustion chamber through the air intake system. Any dirt in the engine
can cause engine wear and eventually lead to engine failure. Therefore, an
air filter, like the fuel filter, is also a critical component in any
internal combustion engine. The air filter is inspected with every oil
change and it is changed as needed.
