1. Fuel Pump:
* Listen for the pump: Turn the key to the "on" position (don't start the engine). You should hear a brief whirring sound from the fuel pump, usually located near the fuel tank. If you don't hear it, the pump might be faulty, or its wiring/fuse is bad.
* Check the fuel pump relay: Locate the fuel pump relay (consult your owner's manual or a wiring diagram). Try swapping it with a known good relay of the same amperage rating.
* Check the fuel pump fuse: Similarly, check the fuse for the fuel pump.
* Check the fuel pump power wire: Use a test light or multimeter to check for power at the pump's connector when the key is on. No power indicates a problem with the wiring or relay.
* Check fuel pressure: This requires a fuel pressure gauge. Hook it up to the fuel line at the carburetor and check the pressure with the key on. The spec should be in your repair manual (typically around 7-9 psi for a carburetor). Low or no pressure points to a faulty pump, clogged filter, or other fuel delivery issue.
2. Fuel Filter:
* Inspect the fuel filter: Locate the fuel filter (often near the fuel pump) and check if it's clogged. A clogged filter will restrict fuel flow. Replace it if necessary.
3. Fuel Lines:
* Inspect fuel lines: Visually inspect the fuel lines for cracks, kinks, or leaks. Any damage will prevent fuel from reaching the carburetor.
4. Carburetor:
* Check the fuel inlet: Make sure the fuel inlet on the carburetor isn't clogged.
5. Other Potential Issues:
* Fuel tank: Though less common, a completely empty tank, a collapsed tank, or debris in the tank could restrict fuel flow.
* Mechanical fuel pump (if equipped): Some older vehicles use a mechanical fuel pump driven by the engine. If yours does, check its operation and condition.
* Wiring issues: There could be a break in the wiring between the ignition switch, fuel pump relay, and the fuel pump itself. A professional mechanic with a wiring diagram can help diagnose this.
Troubleshooting Steps:
1. Start with the easiest checks: Listen for the fuel pump, check the fuse and relay.
2. Check fuel pressure: This is the most definitive test for fuel delivery problems.
3. Visual inspection: Inspect fuel lines and filter for damage or blockages.
4. If all else fails: Consult a repair manual specific to your 1988 Chevy Silverado, or take it to a qualified mechanic.
Safety Precautions:
* Work in a well-ventilated area.
* Gasoline is highly flammable. Avoid sparks or open flames.
* Use appropriate safety glasses and gloves.
Remember that working with fuel systems requires caution. If you're not comfortable performing these checks, it's best to take your truck to a mechanic.
