Replacing Fuel Pump In S10: Step-By-Step Guide

If you're looking to replace the fuel pump on your 2003 S10, you'll need to access the pump, which is located inside the fuel tank. There are a few ways to do this: you can remove the bed of the truck, drop the fuel tank, or cut an access panel in the bed. Each method has its pros and cons, and the right approach may depend on factors such as the equipment you have available, your mechanical expertise, and the condition of your fuel tank.

Before starting, make sure you relieve the fuel system pressure and drain the fuel tank. You'll also need to disconnect the negative battery cable, remove the fuel tank shield and straps, and detach the fuel lines and vapor hose from the pump and tank. Then, you can access the pump through the top of the fuel tank via an access panel in the passenger compartment, or by removing the tank from the vehicle.

It's worth noting that fuel pump replacement is a moderately complicated job, and it may be best performed by a professional mechanic or at a dealership's service department.

Relieve the fuel system pressure

To relieve the fuel system pressure on a 2003 S10, you must first remove the gas cap. Then, start the engine and remove the fuel pump relay. The engine will run out of gas. You can also remove the fuse, but this will only starve the motor of fuel and will not remove the fuel from the rail.

Another method is to follow the fuel lines from the throttle body. About six inches away from the throttle body, there should be a small valve that looks like a tire valve. Put a rag around it to catch any spraying gas, then push the pin down with a screwdriver.

Alternatively, you can relieve the pressure by loosening the fuel filter. Place a bucket underneath it to catch any fuel, then loosen the filter with a wrench.

Finally, you can relieve the pressure by using the Schrader valve.

Drain the fuel tank

To drain the fuel tank of your 2003 S10, you will need to relieve the fuel system pressure. You can then drain the fuel tank through the filler pipe.

Tools you will need:

• Spanner wrench
• New seal for the fuel pump opening

Steps:

• Relieve the fuel system pressure.
• Drain the fuel tank through the filler pipe.
• Support the fuel tank.
• Remove the negative battery cable.
• Remove the shield and tank straps.
• Disconnect the fuel lines and vapor hose from the pump and tank.
• Disconnect the electrical connection from the fuel pump.
• Remove the fuel pump/sending unit assembly by turning the locking ring (located on top of the fuel tank) counterclockwise using a spanner wrench.
• Remove the fuel pump from the fuel lever sending device.
• Install the new fuel pump with a new seal around the opening.
• Reinstall the fuel tank and connect the fuel lines and vapor hose. Torque to: 33 ft. lbs. (45 Nm).
• Reattach the fuel filler neck and clamp.
• Reconnect the negative battery cable.
• Run the engine and check for leaks.

Remove the negative battery cable

To remove the negative battery cable from your 2003 S10, you'll need to follow a few careful steps to ensure your safety and protect the vehicle's electrical system. Here's a detailed guide:

Step 1: Prepare Your Workspace

• Park your S10 in a well-ventilated area, ideally in a garage or shaded spot away from direct sunlight.
• Gather the necessary tools, including a wrench or socket set to loosen and tighten battery terminals.
• Put on safety gear, such as gloves and eye protection, to shield yourself from battery acid and any tools.

Step 2: Locate the Negative Battery Cable

• Open the hood of your 2003 S10 and identify the battery. It is typically located near the engine, in the engine bay.
• Identify the negative battery cable. It is usually black and marked with a "-" symbol or a black clamp. The positive cable is typically red and marked with a "+" symbol.

Step 3: Disconnect the Negative Battery Cable

• Loosen the nut or bolt that secures the negative battery cable clamp to the battery terminal using your wrench or socket. Turn it counterclockwise to loosen.
• Once it's loose, carefully lift the cable straight up and away from the battery terminal. Be cautious not to let the cable touch any metal parts of the vehicle to avoid creating a short circuit.
• If there is any corrosion or residue on the terminal, clean it with a wire brush or a mixture of baking soda and water.

Step 4: Secure the Cable

• After disconnecting the cable, make sure to secure it away from the battery to prevent accidental contact. You can use tape or a cable tie to hold it in place.
• Ensure that the cable does not touch any metal surfaces or hang close to the battery.

Step 5: Reinstallation (if necessary)

• If you need to reinstall the negative battery cable, first ensure that the battery terminal is clean and free of corrosion.
• Carefully place the negative cable back onto the corresponding negative terminal.
• Tighten the nut or bolt securely with your wrench or socket, but be careful not to over-tighten, as this can damage the terminal or cable.

Remember, always exercise caution when working with your vehicle's electrical system. If you're uncomfortable performing these steps, it's best to consult a qualified mechanic or seek advice from a trusted auto repair forum.

Disconnect the fuel lines and vapour hose

To disconnect the fuel lines and vapour hose on a 2003 S10, you will need to relieve the fuel system pressure. Drain the fuel tank through the filler pipe and support the fuel tank. Remove the negative battery cable, shield and tank straps. You can then disconnect the fuel lines and vapour hose from the pump and tank.

To disconnect the fuel lines, you will need to first relieve the pressure in the lines. This can be done by depressing the valve in the centre of the quick-connect fitting. You can then pull the lines off by hand or with a pair of pliers. Be careful not to damage the O-rings on the lines.

The vapour hose is connected to the vapour valve on the fuel tank. To disconnect it, simply pull the hose off the valve by hand or with a pair of pliers.

Once the fuel lines and vapour hose are disconnected, you can remove the electrical connection from the fuel pump and then remove the fuel pump/sending unit assembly by turning the locking ring counterclockwise using a spanner wrench.

Remove the electrical connection from the fuel pump

To remove the electrical connection from the fuel pump of your 2003 S10, you will first need to relieve the fuel system pressure and drain the fuel tank through the filler pipe. Support the fuel tank and remove the negative battery cable, shield, and tank straps. Then, remove the fuel lines and vapour hose from the pump and tank.

Now, you can remove the electrical connection from the fuel pump. First, locate the locking ring on top of the fuel tank. Using a spanner wrench, turn the locking ring counterclockwise to loosen it. This will allow you to remove the fuel pump/sending unit assembly from the fuel tank. With the assembly removed, you can now access and disconnect the electrical connection from the fuel pump.

Be sure to install a new seal when you reinstall the fuel pump and assembly.

Frequently asked questions