Here's how to do it:
1. Safety First:
* Disconnect the negative battery terminal. This is crucial to prevent accidental sparking and fire.
* Work in a well-ventilated area. Fuel vapors are dangerous.
* Wear safety glasses. Fuel can spray unexpectedly.
* Have a fire extinguisher nearby. Better safe than sorry.
2. Gather Your Tools:
* Fuel pressure gauge: This is specifically designed to measure fuel pressure. You'll need one that's compatible with the fuel pressure range of your Fiero (consult your repair manual for the specification, usually around 30-45 PSI). It should come with the appropriate adapter for your fuel rail's Schrader valve (looks like a tire valve stem).
* Wrench or socket: You might need this to disconnect the fuel line if your gauge doesn't have a quick-connect fitting.
* Shop rags or paper towels: To clean up any spilled fuel.
* Repair Manual (highly recommended): This will provide specific pressure readings and locations for your Fiero's fuel system.
3. Locate the Fuel Rail Schrader Valve:
The fuel rail is a metal pipe on the intake manifold that distributes fuel to the injectors. The Schrader valve is usually located on the fuel rail itself, and resembles a tire valve stem. Your repair manual will show the exact location.
4. Attach the Fuel Pressure Gauge:
* Carefully remove the valve cap from the Schrader valve on the fuel rail.
* Connect the fuel pressure gauge's fitting securely to the Schrader valve. Be sure it's tight to avoid leaks.
5. Crank the Engine:
* Reconnect the negative battery terminal.
* Turn the ignition key to the "ON" position (don't crank the engine yet). This will prime the fuel pump and build up pressure. Let it sit for a minute or two.
* Crank the engine for a few seconds. This should increase the pressure even further and allow you to read the gauge. You may need to repeat the cycle a few times to be sure of an accurate pressure reading
6. Read the Pressure:
Observe the reading on the fuel pressure gauge. Compare this to the specifications in your repair manual.
7. Release the Pressure:
* Turn the ignition to the "OFF" position.
* Carefully depress the Schrader valve's pin with a small tool or the gauge's release button (some gauges have a release button, others don't). This will slowly release the fuel pressure. Be careful—fuel might spray out.
8. Reassemble:
* Replace the Schrader valve cap.
Interpreting the Results:
If the fuel pressure is outside the specified range in your repair manual, you may have a problem with the fuel pump, fuel pressure regulator, fuel filter, or other components in the fuel delivery system. Consult a repair manual for troubleshooting steps.
Important Note: This procedure provides a general guideline. Always consult your vehicle's repair manual for the specific procedures and pressure specifications for your 1985 Pontiac Fiero SE 2.8. If you are uncomfortable performing this procedure yourself, take your vehicle to a qualified mechanic.
