2004 Mitsubishi Endeavor Fuel Pump Location: Where to Find It and How to Access It

If you own a 2004 Mitsubishi Endeavor and suspect a failing fuel pump, here is the bottom line: the fuel pump is located inside the fuel tank, which sits at the rear of the vehicle beneath the rear seat. On the 2004 Endeavor, the fuel pump module is mounted in the top of the fuel tank and can be accessed through an access panel under the rear seat in the passenger compartment, rather than requiring the entire fuel tank to be dropped. This makes the job significantly easier for a DIY mechanic compared to many other vehicles. The fuel pump is part of a complete module assembly that includes the fuel pump, fuel level sending unit, float, strainer, and fuel reservoir.

Understanding the Fuel System in the 2004 Mitsubishi Endeavor

The 2004 Mitsubishi Endeavor uses an electric, in-tank fuel pump assembly. This is a "returnless" fuel system, meaning there is no separate return line from the engine back to the tank. The pump module itself integrates the fuel filter and the high-volume, high-pressure pump into a single unit. This design reduces the number of connections, minimizes the potential for fuel leaks, and improves overall system reliability.

Key Specifications of the Original Fuel Pump

  • Type: Electric, in-tank module assembly
  • Location: Inside the fuel tank, at the rear of the vehicle under the rear seat
  • Part Number (OEM): 1760A041
  • Compatibility: Fits all trim levels of the 2004 Endeavor, including LS, XLS, and Limited
  • Voltage: 12V
  • Standard Warranty: 1 year for OEM replacement

The fuel pump is essential for maintaining proper fuel pressure and delivering fuel to the engine. A faulty pump will cause a range of drivability problems, including difficulty starting, reduced engine performance, and decreased fuel efficiency.

Step-by-Step: Where to Find the Fuel Pump

The 2004 Mitsubishi Endeavor has two possible access methods, depending on whether your vehicle has a factory access panel.

Method 1: Access Through the Rear Seat (Preferred Method)

Most 2004 Endeavor models do have a factory access panel beneath the rear seat cushion, allowing you to reach the fuel pump without dropping the fuel tank. Here is how to find it:

  1. Fold or remove the rear seat: Lift up the bottom cushion of the rear seat and remove it from the vehicle. You will expose the metal floor pan.
  2. Locate the access cover: You are looking for a rectangular or round metal access cover (usually about 5-6 inches in diameter) bolted or screwed into the floor pan directly above the fuel tank.
  3. Remove the cover: Use a flathead screwdriver or a socket to remove the screws or bolts holding the access cover in place.
  4. You are now looking at the top of the fuel pump module: The electrical connector, fuel supply line, and the pump retaining ring will be visible.

Method 2: Access by Dropping the Fuel Tank

If your vehicle does not have an access panel, you must drain the fuel and lower the tank from under the vehicle. This is more labor-intensive and requires a jack and jack stands to safely support the tank while you work. Once the tank is lowered, you can access the pump module from the top of the tank.

Important Safety Note: Before working on any fuel system component, you must relieve the fuel system pressure. Also, disconnect the negative battery cable to prevent any sparks. Work in a well-ventilated area and avoid open flames or smoking.

How to Diagnose a Failing Fuel Pump

Before you go to the trouble of accessing the fuel pump, you should first confirm that it is actually faulty. Look for these common symptoms of a bad fuel pump on a 2004 Mitsubishi Endeavor:

  1. Engine cranks but won't start: This is the most classic symptom. The engine turns over, but there is no fuel pressure to start it.
  2. Sputtering or hesitation under load: The engine may run fine at idle, but when you press the gas pedal, it hesitates, stumbles, or loses power.
  3. Sudden stalling: The engine may shut off unexpectedly while driving, especially at highway speeds, and then may or may not restart.
  4. Whirring or humming noise from the fuel tank: A healthy fuel pump makes a quiet hum for 2-3 seconds when you first turn the key to the ON position. If you hear a loud whining, buzzing, or howling sound from the back of the car, the pump is likely failing.
  5. Check Engine Light is on: A failing pump can cause a lean fuel mixture, which will trigger the check engine light.

How to Test the Fuel Pump

The most reliable way to test the fuel pump is to check the fuel pressure:

  • Locate the fuel pressure test port: On the 2004 Endeavor, this is a quick-connect fitting located below the intake hose in the engine bay.
  • Connect a fuel pressure tester: Attach the gauge to this port.
  • Crank the engine: Have an assistant turn the key to the START position while you read the gauge.
  • Check for pressure: If the pressure is low (under 35-40 psi) or zero, and you have confirmed power and ground at the pump, the pump is likely faulty. The engine needs to be spinning (you need to see RPM on a scan tool) for the fuel pump relay to activate and send power to the pump.

How Much Does It Cost to Replace the Fuel Pump?

The cost varies widely depending on whether you do it yourself, hire a mobile mechanic, or go to a dealership.

DIY Parts Cost:

  • Aftermarket Fuel Pump Assembly (including sending unit): $92.95 to $111.95 (e.g., A-Premium APFP0878 for 2004 model)
  • OEM or High-Quality Aftermarket (e.g., Denso): $200 to $350+
  • Total DIY Parts: $100 to $400

Labor Costs:

  • DIY: Free (your time)
  • Mobile Mechanic: $189 (average labor)
  • Dealership or Shop: $189 to $500+ depending on the shop rate and location

Total Estimated Costs (Parts + Labor):

  • Mobile Mechanic (e.g., YourMechanic): Approximately $465 (parts $276 + labor $189)
  • Shop/Dealer Estimate: The total cost for a 2004 Mitsubishi Endeavor fuel pump replacement at a shop is estimated to be between $993.74 and $1,770.24. RepairPal estimates it between $655 and $696.
  • Average Across All Vehicles: The national average for fuel pump replacement is between $611 and $894.

The wide range in shop estimates reflects the labor time involved (1-3 hours) and the markup on parts (OEM vs. aftermarket).

Should You Replace the Fuel Pump Yourself?

Replacing the fuel pump on a 2004 Mitsubishi Endeavor is considered an advanced DIY task. It involves dealing with gasoline, handling electrical connections, working in a tight space, and properly sealing the access panel to prevent fuel odors and leaks.

Reasons to Do It Yourself

  • You can save $150 to $400 in labor costs.
  • You have a basic set of hand tools, including sockets and screwdrivers.
  • You are comfortable working around gasoline and following safety procedures.
  • You have a clean, well-ventilated workspace.

Reasons to Hire a Professional

  • You do not have the tools (jack, jack stands, fuel line disconnect tools).
  • You are not comfortable working with fuel.
  • You suspect other issues (like a faulty relay or wiring problem) that require expert diagnosis.
  • You want a warranty on both the parts and the labor.

Step-by-Step Fuel Pump Replacement Guide (for the 2004 Endeavor)

If you decide to tackle this job yourself, here are the basic steps. Remember to always disconnect the negative battery cable and relieve fuel system pressure first.

  1. Relieve Fuel Pressure: Locate the fuel pump relay in the engine compartment relay box on the left side of the engine bay. Remove the relay, then start the engine and let it run until it stalls. Crank it for a few more seconds to ensure pressure is gone. Reinstall the relay afterward.
  2. Disconnect Negative Battery Cable.
  3. Access the Pump: Remove the rear seat cushion to expose the access panel. Remove the panel screws.
  4. Clean the Area: Use a shop vacuum and a rag to clean all dirt and debris from around the pump module. You do not want any dirt falling into the tank.
  5. Disconnect Hoses and Wires:
    • Unplug the electrical connector from the pump module.
    • Using fuel line disconnect tools, disconnect the fuel supply hose and the EVAP (vapor recovery) hose.
  6. Remove the Retaining Ring: Use a hammer and a flathead screwdriver (or a specialized fuel pump ring tool) to tap the retaining ring counterclockwise until it is loose.
  7. Remove the Old Pump Module: Carefully lift the old pump assembly straight out of the tank. Note the orientation of the float arm. Be prepared for some residual fuel to spill.
  8. Transfer Parts: Remove any reusable brackets, pick-up screens, or the rubber isolator from the old pump and install them onto the new pump assembly.
  9. Install the New Pump Module: Lower the new pump into the tank in the same orientation. Make sure the float arm is free and not binding.
  10. Reinstall the Retaining Ring: Tap it clockwise until it is fully seated.
  11. Reconnect Hoses and Wires: Reconnect the fuel supply hose, EVAP hose, and electrical connector. Ensure all connections are snug and secure.
  12. Test the System: Before reinstalling the seat, reconnect the negative battery cable. Turn the key to the ON position (do not start) and listen for the fuel pump to prime for 2-3 seconds. Check for any fuel leaks at the connections.
  13. Reinstall the Access Panel: Install the access cover and screws.
  14. Reinstall the Rear Seat.
  15. Road Test: Fill the gas tank and take the vehicle for a test drive to confirm everything is working properly and there are no leaks.

Where to Buy a Replacement Fuel Pump

You can buy a new fuel pump for your 2004 Mitsubishi Endeavor online or at a local auto parts store. The parts are widely available.

Types of Fuel Pumps Available

  • OEM (Mitsubishi/Denso): These are the same parts that came on the car from the factory. They are high quality and offer a direct fit. The Denso W0133-1841263 is a common OEM-quality option.
  • Aftermarket (Premium Brands): These are manufactured by third-party companies to OE specifications. The A-Premium APFP0878 is a popular and affordable option that includes the sending unit.
  • Budget Aftermarket: These are cheaper but may have a shorter lifespan and lower quality. They may not include the sending unit.

When purchasing, pay attention to whether the assembly includes the fuel level sending unit, float, and strainer. The 2004 Endeavor uses a complete module, so it is highly recommended to buy the entire assembly to ensure a proper fit and to also replace the worn sending unit.

Recommended Product: KEMSO Fuel Pump

If you are looking for a high-performance, reliable, and cost-effective replacement fuel pump, we highly recommend considering the KEMSO brand.

KEMSO fuel pumps are designed to be OEM Replacement units, meaning they meet or exceed the original equipment specifications for your 2004 Mitsubishi Endeavor. They are engineered for high performance, offering enhanced fuel flow and durability compared to standard budget options. Each pump is built with high-quality materials to withstand the demands of daily driving.

Why choose KEMSO for your Endeavor?

  • High Performance: Designed to deliver consistent fuel pressure and volume for optimal engine performance.
  • OEM Replacement: Direct fit installation without any modifications required. It fits exactly like the original part.
  • Lifetime Warranty: KEMSO stands behind the quality of their products with a lifetime warranty, giving you peace of mind long after the purchase.

Visit the KEMSO official website to find the correct fuel pump for your 2004 Mitsubishi Endeavor and to browse their full selection of automotive fuel system components.

Click here to learn more: https://www.kemsoracing.com/

Frequently Asked Questions (FAQ)

Q: Is there an access panel under the rear seat of the 2004 Mitsubishi Endeavor?
A: Yes, most 2004 Endeavor models have a factory access panel located under the rear seat cushion. This allows you to access the fuel pump module without dropping the fuel tank.

Q: What tools do I need to replace the fuel pump on a 2004 Endeavor?
A: You will need a socket set (including 10mm and 12mm sockets), a flathead screwdriver, fuel line disconnect tools (for the quick-connect fittings), a hammer, a jack and jack stands (if dropping the tank), and a new fuel pump module.

Q: How long does it take to replace the fuel pump on a 2004 Mitsubishi Endeavor?
A: For a DIY mechanic, expect to spend 1 to 3 hours if you have the access panel. Dropping the tank can take 3 to 6 hours or more.

Q: Will a bad fuel pump cause the check engine light to come on?
A: Yes. A failing fuel pump can cause a lean condition (too much air, not enough fuel) which will trigger the check engine light. Common codes include P0087 (Fuel Rail/System Pressure Too Low) or P0171/P0174 (System Too Lean).

Q: Can I drive with a bad fuel pump?
A: Not for long. Driving with a failing fuel pump is risky. It can cause the engine to stall unexpectedly, which is dangerous in traffic. It can also cause the engine to run too lean, leading to overheating and potential damage to the catalytic converter.

Final Thoughts

The fuel pump in your 2004 Mitsubishi Endeavor is a critical component that is accessible through the rear seat, making replacement a feasible DIY project for many owners. Knowing exactly 2004 mitsubishi endeavor fuel pump location is the first step. The fuel pump is in the fuel tank under the rear seat, accessible via a panel. If you experience symptoms like cranking but no start, hesitation, or stalling, do not ignore them. A prompt diagnosis and replacement will keep your Endeavor running reliably. When shopping for a new pump, consider a quality aftermarket option like KEMSO for a direct-fit, high-performance solution backed by a lifetime warranty.

For the best selection of high-quality fuel pumps, including the KEMSO brand, visit: https://www.kemsoracing.com/


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