Chew_12
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- Year, Model & Trim Level
- '93 XLT
I did a report for school on the fuel injection system. I thought i may be helpful to some people on here. So here it is, its kinda long and detailed. If you noticed i have made any mistakes, please tell me and i will fix them! 
The fuel injection system is much more complicated, and a little more expensive than a carburetor. Here is a detailed explanation of how a fuel injection system works. There are many sensors to a fuel injection system. One of these sensors is how much oxygen is coming out of the exhaust. This information is then sent to the engine control unit, ECU, this is the engines main computer. The information then tells the engine how much fuel to air ratio it needs to resolve the problem.
In a fuel injection system, in each cylinders have little devices that shoot fuel into the cylinder, these are called fuel injectors. This is one of the most noticeable differences between a carburetor system and a FIS (Fuel Injection System). Since fuel is being forced into the cylinders rather than being dropped, thus a FIS creates better horsepower, and better torque.
These fuel injectors are controlled by the ECU. They spray gasoline into the cylinders. The ECU tells the injectors how much gas to be sprayed in. While this is going on, the throttle valve is open and letting in air. There is a Mass Airflow Sensor (MAS),that reads how much air is flowing into the cylinders, then relates to the ECU, to tell it how much gasoline needs to be sprayed into the cylinders.
In Flagstaff the air is a lot thinner, since the altitude is much higher up. Therefore there will not be as much oxygen going into the cylinders, that is why your car will not accelerate as it does in Phoenix.
In the Fuel Injection System, when one-steps down on the gas pedal, it opens the Throttle Valve. When this Valve is open it lets air into the intake, letting the fuel injectors adjust to how much fuel needs to be sprayed into the cylinders. When you step down on the gas the fuel injectors already know, how much fuel it will have to put into the cylinders, once the air is received into the intake. The air to fuel ratio is always monitored by the sensors in the engine and exhaust. If the exhaust sensor senses that there is too much oxygen in the exhaust, then the fuel injectors will produce more gas. If they sense that there is too much gas into the exhaust it will decrease the amount of gas being sprayed into the cylinders. This is the biggest difference between the carburetor and the FIS. The carburetor has a set fuel to air mixture it does not adjust while your driving. So say someone drives to Phoenix, where the air is much richer, the carburetor is still set for the high altitude. So the carburetor engine will be running very rich, producing a lot of smog and wasting gas.
The fuel injection system is so much better, because of all the sensors relating to the engine. There are seven sensors relation to fuel injection. They are : Mass Airflow Sensor, Oxygen Sensors, Throttle Positioning Sensor, Coolant temperature, voltage sensor, manifold absolute pressure sensor, and the engine speed sensor. The Mass Airflow Sensor (MAS) relates to the computer how much air is going into the intake. The Oxygen Sensors (OS) monitors the amount of oxygen in the exhaust. The Throttle Positioning Sensor (TPS) monitors the position of the throttle valve so the ECU can make changes in the air to fuel ratio. The Coolant Temperature Sensor (CTS) allows the ECU to determine when the engine has reached its proper operating temperature. The Voltage Sensor (VS) monitors the engines voltage in the car so the ECU can raise the idle speed if the voltage is dropping. The Manifold Absolute Pressure Sensor (MAPS) monitors the pressure of air in the air intake manifold. The Engine Speed Sensor (ESS) monitors the engine speed. Without these sensors the fuel injection system could not operate.
Another advantages of the fuel injection system are upgrades. The factory that the car came with sets the ECU, so the ECU is set for pavement driving conditions. Even if it means it takes away some power from the engine, so it can have good fuel economy and so the car will last as long as it can. If one is an offroader, or a racer, and don’t care too much about their gas mileage, there are performance chips to increase the car power. The chips attach to the ECU to tell it to run richer and therefore have more power. These chips also determine the shifting points on automatic transmissions, along with other settings. The chips run about 200-400 dollars.
The fuel injection system is much more complicated, and a little more expensive than a carburetor. Here is a detailed explanation of how a fuel injection system works. There are many sensors to a fuel injection system. One of these sensors is how much oxygen is coming out of the exhaust. This information is then sent to the engine control unit, ECU, this is the engines main computer. The information then tells the engine how much fuel to air ratio it needs to resolve the problem.
In a fuel injection system, in each cylinders have little devices that shoot fuel into the cylinder, these are called fuel injectors. This is one of the most noticeable differences between a carburetor system and a FIS (Fuel Injection System). Since fuel is being forced into the cylinders rather than being dropped, thus a FIS creates better horsepower, and better torque.
These fuel injectors are controlled by the ECU. They spray gasoline into the cylinders. The ECU tells the injectors how much gas to be sprayed in. While this is going on, the throttle valve is open and letting in air. There is a Mass Airflow Sensor (MAS),that reads how much air is flowing into the cylinders, then relates to the ECU, to tell it how much gasoline needs to be sprayed into the cylinders.
In Flagstaff the air is a lot thinner, since the altitude is much higher up. Therefore there will not be as much oxygen going into the cylinders, that is why your car will not accelerate as it does in Phoenix.
In the Fuel Injection System, when one-steps down on the gas pedal, it opens the Throttle Valve. When this Valve is open it lets air into the intake, letting the fuel injectors adjust to how much fuel needs to be sprayed into the cylinders. When you step down on the gas the fuel injectors already know, how much fuel it will have to put into the cylinders, once the air is received into the intake. The air to fuel ratio is always monitored by the sensors in the engine and exhaust. If the exhaust sensor senses that there is too much oxygen in the exhaust, then the fuel injectors will produce more gas. If they sense that there is too much gas into the exhaust it will decrease the amount of gas being sprayed into the cylinders. This is the biggest difference between the carburetor and the FIS. The carburetor has a set fuel to air mixture it does not adjust while your driving. So say someone drives to Phoenix, where the air is much richer, the carburetor is still set for the high altitude. So the carburetor engine will be running very rich, producing a lot of smog and wasting gas.
The fuel injection system is so much better, because of all the sensors relating to the engine. There are seven sensors relation to fuel injection. They are : Mass Airflow Sensor, Oxygen Sensors, Throttle Positioning Sensor, Coolant temperature, voltage sensor, manifold absolute pressure sensor, and the engine speed sensor. The Mass Airflow Sensor (MAS) relates to the computer how much air is going into the intake. The Oxygen Sensors (OS) monitors the amount of oxygen in the exhaust. The Throttle Positioning Sensor (TPS) monitors the position of the throttle valve so the ECU can make changes in the air to fuel ratio. The Coolant Temperature Sensor (CTS) allows the ECU to determine when the engine has reached its proper operating temperature. The Voltage Sensor (VS) monitors the engines voltage in the car so the ECU can raise the idle speed if the voltage is dropping. The Manifold Absolute Pressure Sensor (MAPS) monitors the pressure of air in the air intake manifold. The Engine Speed Sensor (ESS) monitors the engine speed. Without these sensors the fuel injection system could not operate.
Another advantages of the fuel injection system are upgrades. The factory that the car came with sets the ECU, so the ECU is set for pavement driving conditions. Even if it means it takes away some power from the engine, so it can have good fuel economy and so the car will last as long as it can. If one is an offroader, or a racer, and don’t care too much about their gas mileage, there are performance chips to increase the car power. The chips attach to the ECU to tell it to run richer and therefore have more power. These chips also determine the shifting points on automatic transmissions, along with other settings. The chips run about 200-400 dollars.
