Replacing Fuel Pump In '99 Chevy Wilverado 1500: Step-By-Step Guide

If you're experiencing issues with your 1999 Chevy Silverado 1500's fuel pump, you may need to replace it. A fuel pump's job is to pump fuel to the engine, and it typically lasts for the life of the vehicle. However, there are instances when it can fail, and you'll need to replace it. Signs of a failing fuel pump include a car that won't start, a sputtering engine, or a check engine light coming on.

Replacing a fuel pump can be a moderately complicated job, but with the right tools and knowledge, it can be done at home. There are two common methods for replacing the fuel pump on a Silverado: removing the bed or dropping the fuel tank. This guide will walk you through the steps to replace your fuel pump and get your Silverado running smoothly again.

How to Replace Fuel Pump in 1999 Chevy Wilverado 1500

Drop the fuel tank

Dropping the fuel tank is one of two predominant methods for replacing the fuel pump on a 1999 Chevy Silverado 1500. The other method is to remove the bed.

Step 1: Relieve fuel line pressure

Before starting, put on safety goggles to protect your eyes from gasoline splashes. Next, pull the fuel pump relay from the fuse box and start the vehicle. Let the vehicle run until it shuts down by itself. This will relieve the gas pressure in the line and the pump. Ensure that you work in a well-ventilated area, away from any heat sources, sparks, and open flames. Do not smoke while working around fuel sources.

Step 2: Lift the truck

Use the appropriate lifting points and place the truck on jack stands in the manufacturer's recommended locations on level ground. If you don't have access to a lift, use four jack stands and lift the entire truck, rather than just the rear end.

Step 3: Remove the fuel filler neck from the tank

This step can be a little tricky as the fuel filler neck is in a difficult position to access. The fuel filler neck is located on the driver's side of the tank and above the frame. It is a large-diameter hose connected to the tank with a hose clamp. Use a stubby flat-head screwdriver to loosen the hose clamp, and the fuel filler neck should come off easily.

Step 4: Disconnect the fuel tank lines

Move to the passenger side of the tank and disconnect all the lines going into the top of the tank. Start with the vapor line and pull it off from the charcoal overflow tank. Next, disconnect the larger supply line. These two lines have a similar connector type—squeeze at the base of the connection, and the lines should pop right off with a little wiggling. There are two more lines above the vapor and supply lines that need to be disconnected as well. These lines will also pop right off, but you'll need two hands as there are white connector clips that need to be pushed in simultaneously while the other hand pulls on the hose.

When you remove these hoses, a lot of gasoline will spill from the lines as there will still be some pressure left. Make sure to wear safety goggles to protect your eyes.

Step 5: Disconnect the power lines to the fuel pump

There are two quick-release electrical plugs on top of the fuel tank that power the fuel pump. Disconnect these plugs from the pump.

Step 6: Remove the gas tank straps and lower the tank

Use a 15 mm socket and ratchet with a long extension to remove the gas tank straps. Remove the front strap completely. For the rear strap, you may need an assistant to hold the tank while you remove it, as it will be heavy. If you don't have a helper, you can use a hydraulic floor jack to hold the tank and then lower it carefully when the last strap is removed. It is helpful to have the fuel tank as empty as possible for this step.

Step 7: Lower the tank

With the straps removed, carefully lower the tank to the floor.

Now that you have dropped the fuel tank, you can proceed to remove and replace the fuel pump.

Remove the bed

To remove the bed of your 1999 Chevy Silverado 1500, you will need to first loosen the rear two bed-to-frame bolts. You can do this by turning them three or four times. Next, remove the other six bed-to-frame bolts. Now, disconnect the fuel tank filler hose from the bedside. At this point, you can lift the bed of the truck, exposing the fuel pump on the top of the tank.

It is important to note that you do not need to completely remove the bed to replace the fuel pump. Lifting the bed will give you enough access to replace the fuel pump.

If you do need to completely remove the bed, you will need to first remove the eight bolts holding the bed in place. Once the bolts are removed, you can slide the bed back onto the tires. This will give you clear access to the fuel tank.

When removing the bed, be sure to take the necessary safety precautions. Always work in a well-ventilated area, free of any heat sources, sparks, and open flames. Do not smoke while working around fuel sources.

Disconnect the fuel filler neck

Disconnecting the fuel filler neck is one of the first steps to replacing the fuel pump in a 1999 Chevy Silverado 1500. This step can be a little difficult because the fuel filler neck is in a hard-to-reach position. You will find the fuel filler neck on the driver's side of the tank and above the frame. This large-diameter hose is connected to the tank with a hose clamp. To disconnect the fuel filler neck, use a stubby flat-head screwdriver to loosen the hose clamp. The fuel filler neck should then pull right off fairly easily.

If you are having trouble reaching the hose clamp, you can try using a tool with a longer handle or an angled head. You may also need to adjust your positioning to get a better angle on the hose clamp. Be careful not to apply too much force, as you don't want to damage the hose clamp or the surrounding components.

Once the hose clamp is loosened, you can gently pull on the fuel filler neck to remove it from the tank. Be prepared for some fuel spillage, as there may still be some pressure in the line. It is important to work in a well-ventilated area and wear safety goggles to protect your eyes from any gasoline splash.

If you are having trouble removing the fuel filler neck, you can try wiggling it back and forth to loosen it from the tank. You can also check to make sure there are no obstructions or corrosion preventing it from coming off. If you encounter any issues, it may be helpful to refer to a service manual or seek advice from a mechanic or someone familiar with this type of repair.

Overall, disconnecting the fuel filler neck is a relatively straightforward task, but it requires careful handling due to the flammable fuel in the lines. Always prioritize your safety and take your time with this step to avoid any potential hazards.

Disconnect the fuel tank lines

Disconnecting the fuel tank lines is a crucial step in replacing the fuel pump in a 1999 Chevy Silverado 1500. Here is a detailed, step-by-step guide on how to safely and effectively complete this task:

Step 1: Move to the Passenger Side of the Tank

It is important to position yourself on the passenger side of the fuel tank to access the fuel tank lines safely. This will give you a clear view and working space to disconnect the lines.

Step 2: Disconnect the Vapor Line

Locate the vapor line, which is one of the lines connected to the top of the fuel tank. Using your hands, squeeze the base of the connection and gently wiggle the line to disconnect it from the charcoal overflow tank. It should come off fairly easily with a little force.

Step 3: Disconnect the Supply Line

The supply line is typically larger than the vapor line. Similar to the vapor line, apply pressure to the base of the connection and wiggle it gently until it pops off. Be cautious, as there may still be some pressure left in the line.

Step 4: Disconnect the Remaining Two Lines

There are two additional lines above the vapor and supply lines that need to be disconnected. These lines have white connector clips that must be pushed in simultaneously as you pull on the hoses. Again, be cautious of any residual pressure in the lines.

Step 5: Wear Safety Goggles

When you disconnect the hoses, a significant amount of gasoline will spill from the lines. To protect your eyes from any gasoline splash, it is essential to wear safety goggles throughout this process.

Step 6: Prepare for Gasoline Spill

Have plenty of shop rags or absorbent materials ready to catch the spilling gasoline. It is crucial to work in a well-ventilated area to avoid inhaling fumes. Ensure there are no sources of ignition, sparks, or open flames nearby.

By carefully following these steps, you will successfully disconnect the fuel tank lines in your 1999 Chevy Silverado 1500, preparing you for the next steps in replacing the fuel pump. Remember to prioritize your safety and work in a well-prepared environment.

Disconnect the power lines

To disconnect the power lines of a 1999 Chevy Silverado 1500, follow these steps:

Step 1: Relieve fuel line pressure

Pull the fuel pump relay from the fuse box. Start the vehicle and let it run until it shuts down. This will relieve the gas pressure in the line and the pump. Ensure you are working in a well-ventilated area, free of any heat sources, sparks, and open flames. Do not smoke while working around fuel sources.

Step 2: Lift the truck

Use the appropriate lifting points and place the vehicle on jack stands in the manufacturer's recommended locations on level ground. If you don't have access to a lift, use four jack stands and lift the entire truck, not just the rear end.

Step 3: Remove the fuel filler neck from the tank

The fuel filler neck is located on the driver's side of the tank, above the frame. It is connected to the tank with a hose clamp. Use a stubby flat-head screwdriver to loosen the hose clamp, and then remove the fuel filler neck.

Step 4: Disconnect the fuel tank lines

Move to the passenger side of the tank and disconnect all lines going into the top of the tank. Start with the vapor line, followed by the larger supply line. These lines have similar connectors that you'll need to squeeze at the base to disconnect. There are two more lines above the vapor and supply lines that need to be disconnected as well. These lines have white connector clips that need to be pushed in while pulling on the hose. Wear safety goggles during this step, as a lot of gasoline will spill from the lines.

Step 5: Disconnect the power lines to the fuel pump

There are two quick-release electrical plugs on top of the fuel tank that power the fuel pump. Disconnect these plugs from the pump.

Step 6: Remove the gas tank straps and lower the tank

Use a 15 mm socket and ratchet with a long extension to remove the gas tank straps. Remove the front strap completely. For the rear strap, you may need an assistant to hold the tank while you remove it, as it will be heavy. If you don't have help, use a hydraulic floor jack to support the tank and lower it carefully. It is recommended to have as empty of a fuel tank as possible for this step.

By following these steps, you will be able to safely disconnect the power lines of your 1999 Chevy Silverado 1500's fuel pump.

Frequently asked questions