There are two parts to the fuel system. One is the delivery system which is the fuel pump and injectors and the second part would incorporate the air system (the way the air enters your engine). These parts would include the fuel pump, fuel filter, fuel injectors and fuel pressure regulators. The air system would include the air filter, mass air flow sensor, throttle plates, idle air control motor, intake runners and intake valves.
Signs that you may have a problem:
- Rough idle
- Hard start
- Poor power
- Poor acceleration
- Poor fuel economy
- Ping (pre ignition detonation)