Fuel System Description: Notes

The fuel system is comprised of two subsystems. The fuel supply system and the fuel metering system. The correct amount of fuel can not be delivered to the engine cylinders without the supply of air from the air intake system. The powertrain control module (PCM), along with the information sensors and switches, controls the activity between all three systems.

The following are the main components of the vehicle's fuel supply system:

• The fuel rail assembly
• The fuel pressure regulator
• The fuel pump
• The fuel tank
• The fuel filter
• The fuel feed pipes and hoses
• The fuel return pipes and hoses

This vehicle is equipped with a sequential fuel injection (SFI) system. The function of the fuel metering system is deliver the correct amount of fuel to the engine under all operating conditions. The main component of the vehicle's fuel metering system is the fuel injectors. There is one fuel injector for each cylinder. The fuel injectors are controlled sequentially by the PCM. The PCM bases the control of the fuel injectors on several important engine parameters. These engine parameters include the following:

• The mass air flow (MAF) sensor
• The intake air temperature (IAT) sensor
• The engine coolant temperature (ECT) sensor
• The throttle position (TP) sensor
• The engine speed (RPM)
• The heated oxygen sensor (HO2S)

Callout	Component Name
1	Left Bank Fuel Injectors
2	Left Bank Fuel Rail
3	Fuel Pressure Regulator
4	Fuel Return Pipes and Hoses
5	Fuel Pump
6	Fuel Filter
7	Fuel Pressure Gauge Adapter J 34730-75
8	Fuel Pressure Gauge J 34730-1A
9	Right Bank Fuel Injectors
10	Right Bank Fuel Rail
11	Fuel Crossover Pipe

The air intake system provides measured clean air to each cylinder for proper mixture with the pressurized fuel. The following are the main components of the vehicle's air intake system:

• The throttle body assembly
• The air cleaner (ACL) assembly
• The air filter element
• The air inlet supply ducts
• The intake manifold and plenum

The engine is designed to use only unleaded fuel. Unleaded fuel must be used for proper emission control system operation. Using unleaded fuel will also decrease spark plug fouling and extend engine oil life. Leaded fuel can damage the emission control system. The use of leaded fuel can result in the loss of emission warranty coverage.

This vehicle's fuel system is equipped with an evaporative emission control system that minimizes the release of fuel vapors to the atmosphere. For more information on this system, refer to Evaporative Emission (EVAP) Control System Description .