To find the fuel pump relay, you should:
1. Consult your owner's manual: This is the best place to start. It will show you a diagram of your fuse and relay boxes and identify the fuel pump relay.
2. Check the underhood fuse box: This is the most likely location. The fuse box cover usually has a diagram showing the location of each fuse and relay. Look for a relay labeled "fuel pump," "EFI," or something similar. Sometimes the diagram uses a symbol instead of a name.
3. Look for a separate relay center: Some S10s might have a smaller relay center located elsewhere in the engine compartment.
4. Use a wiring diagram: If you can't find it using the above methods, you can search online for a wiring diagram specific to your 1998 Chevy S10's engine (e.g., 4.3L V6, 2.2L 4-cylinder). This will show you the relay's location and circuit.
Important Note: Working with automotive electrical systems can be dangerous. If you're not comfortable working on your vehicle's electrical system, it's best to take it to a qualified mechanic.