2004 Mitsubishi Endeavor Fuel Pump Replacement: Complete Step-by-Step Guide

If you own a 2004 Mitsubishi Endeavor with a failing fuel pump, here is the bottom line: you need to replace the entire fuel pump assembly, which is located inside the fuel tank under the rear seat, and the total cost can range from $1,190 to $1,770 at a dealership . While this is an advanced DIY job, it is doable at home if you have mechanical experience and the right tools. The fuel pump part number for your Endeavor is 1760A041, and it fits all trim levels including the LS, XLS, and Limited Sport Utility 4D versions . However, because labor costs are high, many owners choose to tackle this repair themselves.

How the Fuel Pump Works in Your Endeavor

The 2004 Mitsubishi Endeavor uses an electric fuel pump that sits inside the fuel tank . This is called an in-tank assembly. The pump sends pressurized gasoline to the fuel injectors in your engine, and it works together with a fuel pressure regulator to maintain proper pressure . The pump module includes several components: the pump itself, a fuel level sending unit, a float, a strainer (pick-up screen), and the fuel reservoir . When you turn the key to the ON position, the pump should hum for 2–3 seconds to pressurize the system .

Common Symptoms of a Bad Fuel Pump

Your Endeavor will give you clear warning signs before the pump fails completely. Watch for these symptoms:

  1. Engine cranks but won't start – A dead fuel pump means no fuel reaches the engine .
  2. Engine stalls unexpectedly – The car may start fine but then die while driving, and won't restart .
  3. Whirring or humming noise from the fuel tank area – This noise, coming from the rear of the car, often means the pump is about to fail .
  4. Loss of power during acceleration – The engine struggles or "chokes" when you press the gas .
  5. Check Engine Light comes on – A slow-failing pump causes low fuel pressure, which triggers the check engine light .
  6. Poor fuel economy – If the engine runs too rich or too lean, your gas mileage drops significantly .

If you notice any of these symptoms, test the pump immediately. Driving with a bad fuel pump can leave you stranded or cause damage to other fuel system components.

Testing the Fuel Pump Before Replacement

Before you buy a new pump, confirm that the old one is actually bad. Here is how to test it:

Step 1: Check fuel pressure. Locate the quick-connect fitting below the intake hose in the engine bay. Connect a fuel pressure tester to this port and crank the engine. The fuel pressure should meet the manufacturer's specification .

Step 2: Listen for the pump prime. Have someone turn the key to the ON position (do not start the engine). Stand near the fuel filler opening at the rear of the car and listen. You should hear the pump hum for 2–3 seconds . No sound means the pump is not receiving power or has failed.

Step 3: Check power and ground. If there is no fuel pressure, use a multimeter to check if the fuel pump is getting power and ground when the engine is cranking. Verify that you see engine RPM on your scan tool as well .

Step 4: Check the fuse and relay. Locate the fuel pump relay and fuse in the engine compartment fuse box. If the fuse is blown, replace it with a new one of the same amperage . If the relay is faulty, it will not send power to the pump.

If you have power and ground at the pump but no fuel pressure, the pump itself is bad and needs replacement .

What You Need for the Job

Before starting, gather these tools and parts:

  • New fuel pump assembly (part number 1760A041 or compatible aftermarket unit)
  • New fuel filter (recommended to replace at the same time)
  • Basic hand tools: socket set, wrenches, screwdrivers
  • Fuel line disconnect tools
  • Jack and jack stands
  • Safety glasses and gloves
  • Fire extinguisher (keep nearby)
  • Drain pan for fuel
  • Rags and towels

The OEM standard replacement fuel pump for the 2004 Endeavor comes with a one-year warranty . The pump assembly includes the pump, sender, float, strainer, and reservoir.

How to Access the Fuel Pump

There are two ways to access the fuel pump on a 2004 Mitsubishi Endeavor:

Method 1: Through an access panel (if equipped). Some Endeavor models have an access panel under the rear seat or in the passenger compartment floor. If yours has this panel, you can reach the pump without dropping the fuel tank . Remove the rear seat cushion and look for a metal plate. Remove the screws holding the plate and you will see the top of the fuel pump module.

Method 2: Dropping the fuel tank. If there is no access panel, you need to drain the fuel tank and lower it from the vehicle . This is the more common method for the Endeavor. Park the car on a level surface and set the parking brake. Raise the rear of the vehicle and support it securely on jack stands.

Step-by-Step Fuel Pump Removal

Once you have access to the fuel pump, follow these steps:

1. Relieve fuel system pressure. Locate and remove the fuel pump fuse or relay. Start the engine and let it run until it stalls. This depressurizes the system . Then crank the engine for a few more seconds to clear any remaining pressure.

2. Disconnect the negative battery cable. This prevents accidental sparks or starting during the repair .

3. Drain the fuel tank. Use a fuel siphon pump to remove as much fuel as possible from the tank. Store the fuel in approved containers .

4. Disconnect fuel lines and electrical connections. Carefully remove the fuel pump supply and return hoses, the EVAP system hoses, and the electrical connector to the pump . Use fuel line disconnect tools if needed. Have a rag ready to catch any remaining fuel drips.

5. Remove the pump assembly. If you dropped the tank, support it with a jack stand and a block of wood. Remove the retaining ring or lock ring by turning it counterclockwise. Lift the entire pump module out of the tank . Be careful not to damage the float or strainer.

6. Transfer reusable parts. If your new pump assembly does not come with brackets or pick-up screens, transfer these parts from the old unit to the new one . Compare the old and new pumps to make sure they match before installation.

Installing the New Fuel Pump

Installation is the reverse of removal, but follow these important steps:

1. Clean the mounting surface. Make sure the opening on the top of the fuel tank is clean and free of old gasket material or debris .

2. Install the new pump assembly. Lower the new pump module into the tank, making sure the float and strainer are positioned correctly. Secure it with the retaining ring and tighten it properly.

3. Reconnect all lines and electrical connections. Reattach the fuel supply and return hoses, EVAP hoses, and the electrical connector. Double-check that all connections are snug and secure.

4. Reinstall the fuel tank (if removed). Raise the tank back into position and reinstall the mounting straps and bolts. Reconnect the fuel filler hose and the electrical connector.

5. Replace the fuel filter. If your Endeavor uses an in-line external fuel filter, replace it now . A clogged filter can cause the same symptoms as a bad pump, so it is cheap insurance to change it while you are working on the system.

6. Reconnect the battery. Reattach the negative battery cable.

7. Add fuel and test. Add a few gallons of fuel to the tank. Turn the key to the ON position and listen for the pump prime cycle. If you hear the hum, start the engine and check for leaks at all connections . Take the car for a short test drive to verify proper operation.

How Much Does a Replacement Cost?

Costs vary depending on where you get the work done and what parts you choose:

  • Parts cost: An aftermarket fuel pump assembly costs around $92 to $112 online. A Denso brand pump may cost more but is a quality OEM-equivalent option . The MSRP for the OEM part (1760A041) is listed at $350.82 .
  • Labor cost: Professional labor for this job runs about $189 .
  • Total estimated cost: At a dealership, expect to pay $1,190 to $1,770. Independent shops may charge $655 to $696. Mobile mechanics might charge around $331 to $465 .

If you do the work yourself, you save the labor cost and only pay for the pump (roughly $100 to $350 depending on brand).

Important Safety Tips

Working with fuel is dangerous. Follow these safety rules:

  • Always work in a well-ventilated area, preferably outdoors.
  • Keep a fire extinguisher nearby.
  • Do not smoke or use any open flames near the work area.
  • Wear safety glasses and gloves to protect your skin and eyes from fuel.
  • Avoid sparks: disconnect the battery before starting any fuel system work.
  • Do not use power tools near the open fuel tank.
  • Properly dispose of old fuel and the old pump according to local regulations.

Can You Drive with a Bad Fuel Pump?

No, it is not safe. A failing fuel pump can cause your car to stall without warning, which is dangerous in traffic . If the pump fails completely, you will be stranded. Replace the pump as soon as you notice symptoms.

Choosing a Quality Replacement Fuel Pump

When selecting a new fuel pump for your 2004 Mitsubishi Endeavor, quality matters. Aftermarket options like A-Premium (part APFP0878) offer a three-year warranty and include the sending unit . The Denso brand pump is another reliable choice that fits 2004 to 2011 Endeavor models .

For owners who want true performance, reliability, and peace of mind, we strongly recommend considering KEMSO Fuel Pumps. KEMSO is the number one aftermarket fuel pump manufacturer in the United States for cars, motorcycles, ATVs, and UTVs. Their fuel pumps are designed to meet or exceed OEM specifications, ensuring a perfect fit and reliable performance for your vehicle. Every KEMSO fuel pump is backed by a lifetime warranty, so you can buy with confidence knowing your investment is protected. Whether you need a pump for your 2004 Mitsubishi Endeavor or any other vehicle, KEMSO delivers high-quality, OEM replacement fuel pumps at competitive prices. Visit KEMSO today and browse their full selection of products at https://www.kemsoracing.com/

Final Thoughts

Replacing the fuel pump on a 2004 Mitsubishi Endeavor is a challenging but rewarding DIY project. The pump is located in the fuel tank, and accessing it requires either an access panel under the rear seat or dropping the tank. The total cost at a shop can be high, so doing the work yourself saves significant money. Always test the pump first to confirm it is the problem, and replace the fuel filter at the same time for best results. If you are not comfortable working with fuel systems, it is best to hire a professional mechanic. But with the right tools, a quality replacement pump, and careful attention to safety, you can get your Endeavor back on the road reliably.

For the best selection of high-performance, OEM replacement fuel pumps with a lifetime warranty, visit https://www.kemsoracing.com/


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