The exact procedure might vary slightly depending on the engine (5.7L or other) and whether you have a specific fuel pump module or an in-tank assembly, but the general steps are as follows:
1. Safety First:
* Disconnect the negative battery terminal. This is crucial to prevent sparks.
* Ventilate the area. Work in a well-ventilated area or outdoors.
* Wear safety glasses and gloves. Protect yourself from fuel spills and sharp metal.
* Have a fire extinguisher nearby. Be prepared for any potential fire.
2. Accessing the Fuel Pump:
* Locate the fuel pump access panel. This is usually located under the rear passenger seat (or under the carpet in the cargo area in some models) . Consult your owner's manual for the precise location. You'll likely need to remove the seat or some interior trim to gain access.
* Lower the fuel tank (Optional, but often easier): Some mechanics prefer lowering the fuel tank to gain better access, particularly if there's limited room in the access panel. This requires supporting the tank with jack stands and disconnecting the fuel lines, filler neck, and tank straps. This is more involved and requires additional tools.
3. Removing the Fuel Pump:
* Disconnect the electrical connector: Carefully unplug the electrical connector from the fuel pump.
* Disconnect the fuel lines: This is critical. Use fuel line disconnect tools to carefully separate the fuel lines from the pump. Have rags or absorbent material ready to catch any spilled fuel.
* Disconnect the fuel level sender (if applicable): This is a float-type sensor that measures fuel level. Disconnect its electrical connector.
* Remove the fuel pump retaining ring (or clamp): This will hold the fuel pump assembly in place. This usually involves a special tool or a careful use of screwdrivers or pliers. Be cautious not to damage the pump or surrounding components.
* Lift out the fuel pump assembly: Once the retaining ring and all lines are disconnected, carefully lift out the fuel pump assembly. It may be somewhat heavy.
4. Replacing the Fuel Pump (If Necessary):
* Install the new fuel pump assembly reversing the removal procedure. Make sure all connections are secure.
5. Reassembly:
* Reinstall the fuel pump retaining ring.
* Reconnect the fuel lines and electrical connectors, ensuring a tight seal on the fuel lines.
* Reinstall the fuel level sender (if applicable).
* Replace the access panel and any interior trim you removed.
* Reconnect the negative battery terminal.
Important Considerations:
* Fuel pressure: Before working on the fuel system, you might want to relieve fuel pressure in the system. Consult your owner's manual for the procedure; some vehicles have a schrader valve on the fuel rail for this purpose.
* Fuel pump module: The 1999 Suburban might have a fuel pump *module* instead of a simple pump. This module contains the pump, the fuel level sensor, and other components. Replacing a module often involves replacing the entire unit.
* Tools: You'll need a variety of tools including screwdrivers, wrenches, possibly a fuel line disconnect tool, and possibly a fuel pump retaining ring tool.
Recommendation: If you're not comfortable performing this procedure, it's best to take your Suburban to a qualified mechanic. Working with fuel systems is inherently risky, and a mistake can lead to fire or injury. Consult your owner's manual for specific details and diagrams relating to your vehicle's fuel system.
