Fuel system
Fuel system is an overview of the fuel delivery system used in the Pontiac Fiero.
The Fiero fuel system includes the fuel tank, fuel pump, sending unit, fuel lines, fuel filter, fuel rail or throttle body fuel feed, injectors or throttle body injector, fuel pressure regulator, fuel pump relay, oil pressure switch circuit, and related wiring.
Overview
The Fiero used electronic fuel injection throughout production, but the system differs between the four-cylinder and V6 engines.
The 2.5L four-cylinder engine used throttle body injection, while the 2.8L V6 used multi-port fuel injection.
Fuel system problems can cause no-start conditions, hard starting, poor idle, hesitation, stalling, fuel smell, rich or lean running, or loss of power.
Major components
- Fuel tank
- Fuel pump
- Fuel sending unit
- Fuel filter
- Fuel lines
- Fuel pump relay
- Oil pressure switch
- Fuel pressure regulator
- Fuel injectors
- Throttle body injection
- Multi-port fuel injection
Four-cylinder fuel system
The 2.5L four-cylinder Fiero used throttle body injection.
Related topics:
- 2.5L Iron Duke
- Throttle body injection
- Fuel injector
- Fuel pressure specifications
- Idle problems
- No-start diagnosis
V6 fuel system
The 2.8L V6 Fiero used multi-port fuel injection.
Related topics:
- 2.8L V6
- Multi-port fuel injection
- Fuel rail
- Fuel injectors
- Cold start injector
- Fuel pressure regulator
- Fuel pressure test
Common fuel system topics
- Fuel pump problems
- Fuel pressure test
- Fuel filter replacement
- Fuel injector problems
- Fuel smell
- Hard starting
- No-start diagnosis
- Stalling
- Rich running
- Lean running
Electrical control
The fuel pump is controlled electrically. Fuel pump diagnosis may involve the fuel pump relay, oil pressure switch circuit, ECM control, fuses, grounds, wiring, and the ALDL fuel pump test terminal.
Related topics:
Service procedures
- Fuel filter replacement
- Fuel pressure test
- Fuel pump replacement
- Fuel tank removal
- Fuel injector cleaning
- Fuel line inspection
Safety
Fuel system work should be done carefully because gasoline is flammable and fuel systems can remain pressurized after the engine is shut off.
Before opening the fuel system, pressure should be relieved safely and ignition sources should be avoided.