2004 Mitsubishi Endeavor Fuel Pump Location: Complete Guide to Finding and Replacing It

If you own a 2004 Mitsubishi Endeavor and need to locate the fuel pump, here is the direct answer: the fuel pump module sits inside the fuel tank, which is mounted under the rear of the vehicle beneath the rear seat area. In most cases, you can access it by removing the rear seat cushion and opening an access panel in the floor pan, though some models may require dropping the fuel tank entirely. This guide walks you through the exact location, how to confirm the pump is failing, what replacement costs to expect, and how to complete the job safely.

Understanding the Fuel Pump System in Your 2004 Endeavor

The 2004 Mitsubishi Endeavor uses an in-tank electric fuel pump assembly that combines the pump, fuel level sender, float, strainer, and fuel reservoir into one module . This module is positioned at the top of the fuel tank and serves as the single delivery point for pressurized fuel to the engine . Mitsubishi designed this as a returnless fuel system, meaning there is no separate return line running back to the tank. Instead, the pump pushes fuel forward through a single supply line, and excess pressure is managed internally . The fuel pressure regulator is integrated directly into the fuel pump assembly inside the tank, so there is no separate external regulator to service .

The fuel system operates at approximately 58 psi under normal conditions and uses regular unleaded gasoline with an octane rating of 87 or higher . Because the pump is submerged in fuel, it relies on the gasoline for cooling and lubrication. Running the tank consistently low can cause the pump to overheat and fail prematurely.

Where Exactly Is the Fuel Pump Located?

The fuel pump module is mounted in the top of the fuel tank, which sits at the rear of the vehicle underneath the floor pan. There are two ways to reach it depending on your specific vehicle's configuration :

Method 1: Access Panel Through the Passenger Compartment (Preferred)
Many 2004 Endeavor models have a service access panel cut into the floor pan beneath the rear seat. To access the pump this way:

  1. Fold or remove the rear seat bottom cushion
  2. Locate the stamped metal access cover in the floor
  3. Remove the screws or bolts holding the cover in place
  4. You will see the top of the fuel pump module with its electrical connector and fuel lines

Method 2: Dropping the Fuel Tank
If your vehicle does not have an access panel, you must drain the fuel tank and lower it from the vehicle to reach the pump . This is more labor-intensive and requires a jack, jack stands, and a block of wood to support the tank safely . The tank must be completely drained before removal, and you will need to disconnect the filler neck hose, EVAP system hoses, fuel supply line, and all electrical connections before lowering it .

Common Symptoms of a Failing Fuel Pump

Before you tear into the vehicle, confirm the pump is actually the problem. A bad fuel pump in a 2004 Mitsubishi Endeavor typically shows these warning signs :

1. Whining Noise from the Fuel Tank
A low-frequency buzzing or whining sound coming from the rear of the vehicle is often the earliest indicator. The pump may still function, but the noise signals that internal components are wearing out.

2. Sputtering Under Acceleration
If the engine feels like it loses power going uphill or when you press the accelerator hard, the pump may not be maintaining enough pressure. Fuel starvation under load is a classic fuel pump failure symptom.

3. Difficulty Starting the Engine
When the pump cannot build adequate pressure, fuel does not atomize properly in the combustion chamber, making the engine hard to start. You may have to crank several times before the engine catches.

4. Engine Stalls or Refuses to Start
A completely failed pump will not deliver any fuel, so the engine will crank but never fire. This happens when the pump motor burns out or the internal pressure regulator fails entirely .

5. Check Engine Light with P0087 Code
The engine computer may log a P0087 trouble code, which indicates the fuel rail pressure is too low . Any oxygen sensor related codes could also point to a lean condition caused by insufficient fuel delivery.

How to Test the Fuel Pump Before Replacement

You do not need to remove the pump to determine if it is bad. Follow these steps to verify the diagnosis :

Step 1: Check Fuel Pressure at the Test Port
There is a quick-connect fitting below the intake hose in the engine bay. Connect a fuel pressure tester here and have someone crank the engine. You are looking for pressure around 58 psi. If the reading stays at zero, the pump is not delivering fuel.

Step 2: Verify Power and Ground at the Pump
If there is no pressure, confirm the pump is receiving voltage when the engine cranks. Use a multimeter to check for power and ground at the pump electrical connector. If power and ground are present but there is no pressure, the pump itself is faulty .

Step 3: Check the Fuel Pump Relay and Fuse
The fuel pump relay is located on the junction block inside the passenger compartment . A blown fuse or failed relay can cut power to the pump entirely. Swap the relay with a known-good one or test for continuity across the fuse before condemning the pump.

Fuel Pump Replacement Cost Breakdown

Replacement costs vary significantly based on where you get the work done and which parts you choose. Here is what you can expect:

Parts Cost
The original equipment fuel pump module carries part number 1760A041 and lists at around $350 for the part alone . Aftermarket assemblies that include the sending unit typically range from $79 to $200 depending on the brand and included components . A replacement fuel pump from a quality aftermarket supplier generally falls in the $100 to $200 range .

Labor Cost
Labor for fuel pump replacement on a 2004 Endeavor is estimated at around $189 at independent shops . Dealership rates will run higher. Mobile mechanic services average about $189 for the same job . Since the job involves fuel system depressurization and tank access, it is not a quick service.

Total Estimated Cost

  • YourMechanic estimate: $465 total, with $276 in parts and $189 in labor
  • RepairPal estimate: $655 to $696 total
  • Shop/Dealer range: $1,190 to $1,770 for the full service at a dealership

The wide price gap comes from parts markup at dealerships versus independent or mobile mechanics. Shopping around can save you several hundred dollars.

Step-by-Step Fuel Pump Replacement Guide

If you have basic mechanical skills and the right tools, replacing the fuel pump yourself is doable. The entire job takes about 2 to 4 hours depending on which access method your vehicle requires.

Tools and Supplies You Will Need:

  • New fuel pump module assembly
  • Fuel pressure gauge
  • Safety glasses and gloves
  • Jack and jack stands
  • Block of wood
  • Screwdrivers and socket set
  • Drain pan for fuel
  • Shop towels

Safety First: Depressurize the Fuel System
Fuel is highly flammable. Before doing anything, relieve the fuel system pressure. Remove the fuel pump fuse or relay from the junction block, then crank the engine briefly. It will start and stall, indicating the pressure has dropped. Disconnect the negative battery cable afterward to prevent accidental ignition .

Removal Procedure:

  1. Access the Pump – Remove the rear seat cushion and the access panel cover, or drain the tank and lower it if no panel exists

  2. Disconnect Lines and Connectors – Remove the fuel pump supply and return hoses, EVAP system hoses, and the electrical connector from the top of the module

  3. Remove the Retaining Ring – Most Endeavor fuel pumps are held in place by a large threaded ring or lock nut. Use a spanner wrench or hammer and punch to rotate it counterclockwise

  4. Lift Out the Old Assembly – Carefully pull the entire module straight up out of the tank. The float arm and strainer will come with it, so angle it slightly to clear the tank opening

  5. Transfer Reusable Parts – If your new pump does not come as a complete module, move the brackets and pick-up screen from the old pump to the new one

  6. Install the New Pump – Lower the new assembly into the tank, align the float arm, and seat the module properly. Replace the retaining ring and tighten it securely

  7. Reconnect Everything – Reattach the fuel lines, EVAP hoses, and electrical connectors. Make sure all connections are snug but not over-tightened

  8. Reinstall the Tank – If you dropped the tank, raise it back into position, reinstall the straps, and reconnect the filler hose and electrical connections

  9. Test for Leaks – Reconnect the battery, turn the key to the ON position without cranking, and listen for the pump to prime for 2 to 3 seconds. Check all connections for leaks before starting the engine

  10. Run and Recheck – Start the engine and let it idle briefly, then inspect the area around the pump for any fuel odor or dripping. Test drive the vehicle to confirm the new pump performs correctly

Important: While you have the pump out, this is the perfect time to replace the fuel filter if your vehicle uses an external inline filter. Even if it does not, a clogged pickup screen can cause the same symptoms as a failing pump, so inspect the new assembly's strainer carefully .

Preventing Future Fuel Pump Failure

Fuel pumps do not fail without reason. Several habits significantly extend the life of your 2004 Endeavor's fuel pump:

1. Do Not Run on Empty
The fuel pump uses gasoline for cooling. Running the tank below a quarter full regularly causes the pump to run hotter and wear faster. Keep the tank at least a quarter full to maintain proper cooling .

2. Replace the Fuel Filter Per Schedule
The factory service interval calls for a new fuel filter every 30,000 miles or 24 months . A clogged filter forces the pump to work harder, increasing strain and heat buildup.

3. Use Quality Fuel
Stick with major brand gasoline from reputable stations. Contaminated fuel can clog the strainer and accelerate pump wear.

4. Address Check Engine Lights Promptly
If the computer detects lean fuel conditions or low pressure, ignoring the warning will eventually destroy the pump. Diagnostics cost far less than a full replacement .

Choosing the Right Replacement Fuel Pump

When the time comes to replace the pump, you have two primary choices: original equipment from the dealer or a quality aftermarket unit. Here is how to decide:

Original Equipment (OEM): The Mitsubishi part number 1760A041 is the direct factory replacement and guarantees perfect fit and performance. OEM pumps typically carry a one-year warranty from the manufacturer . The downside is the higher price tag.

Aftermarket Options: Quality aftermarket pumps often deliver comparable performance at a lower price. Look for assemblies that include the sending unit, float, and strainer so you do not have to transfer parts between old and new. Top-tier aftermarket brands offer warranties that exceed the factory coverage .

What to Look For:

  1. Complete Module vs. Bare Pump – A complete module with sending unit saves time and eliminates the risk of damaging components during transfer

  2. Voltage Compatibility – Confirm the pump is designed for 12-volt operation to match your vehicle's electrical system

  3. Flow and Pressure Ratings – The pump must deliver at least 36 gallons per hour and 58 psi to meet the engine's demands

  4. Warranty Coverage – A longer warranty indicates the manufacturer stands behind the product

Recommended Supplier: KEMSO Fuel Pumps

For a reliable replacement that combines performance with long-term protection, consider a KEMSO brand fuel pump. KEMSO specializes in high-performance, OEM replacement fuel pumps designed to meet or exceed factory specifications. Every KEMSO pump comes with a lifetime warranty, giving you peace of mind that the part will perform for the life of your vehicle. Whether you are restoring a 2004 Mitsubishi Endeavor or simply replacing a worn-out pump, KEMSO offers a direct-fit solution that installs easily and delivers consistent fuel pressure.

Visit the official KEMSO website to browse their full lineup of fuel pumps for a wide range of vehicles and applications:

https://www.kemsoracing.com/

Final Thoughts

Locating the fuel pump on a 2004 Mitsubishi Endeavor comes down to knowing your vehicle's access configuration. Start by checking for an access panel under the rear seat, and only plan for a fuel tank drop if no panel exists. Test the pump first using the fuel pressure port in the engine bay, and verify that power and ground are present before spending money on a new part. When replacement becomes necessary, weigh the cost of OEM versus aftermarket options, and consider a KEMSO fuel pump for dependable performance backed by a lifetime warranty. Regardless of which route you choose, follow the safety steps for depressurizing the system and testing for leaks. A properly installed fuel pump will keep your 2004 Endeavor running smoothly for many more miles, and if you need a trusted supplier, remember to check the full selection at https://www.kemsoracing.com/ for your replacement needs.


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