Mitsubishi Fuel Pump Relay Location: A Complete Guide to Finding and Replacing It

If you own a Mitsubishi and your engine cranks but won't start, stalls while driving, or you hear no fuel pump noise when turning the key, the fuel pump relay is likely the culprit. The fuel pump relay on most Mitsubishi models is located in the engine compartment fuse box, typically near the battery on the driver's side. For many models like the Montero, L200, and Pajero, the relay is labeled "FUEL PUMP" or "FP" inside the relay box . However, the exact location varies by model and year, so this guide covers the most common Mitsubishi vehicles to help you find it quickly.

What Is a Fuel Pump Relay and Why Does It Matter

The fuel pump relay is an electrical switch that controls power to the fuel pump. When you turn the ignition key, the relay activates and sends battery voltage to the fuel pump, allowing it to pressurize the fuel system. When the relay fails, the fuel pump stops working, and your engine won't get the fuel it needs to run. Common symptoms of a bad fuel pump relay include:

  • Engine cranks but won't start – The most obvious sign
  • No fuel pump noise – You should hear a brief whirring sound from the rear of the vehicle when turning the key to the "ON" position
  • Stalling while driving – The engine may die suddenly, especially under load
  • Intermittent starting issues – The car starts sometimes but not others

General Mitsubishi Fuel Pump Relay Location

For most Mitsubishi vehicles, the fuel pump relay is housed in the engine compartment fuse and relay box . This box is typically located on the left side of the engine bay, right next to the battery. To access it:

  1. Open the hood and locate the fuse box near the battery
  2. Remove the cover by pressing the clips or tabs
  3. Look for a diagram on the inside of the cover that identifies each relay
  4. Find the relay labeled "FUEL PUMP" or "FP"

The relay itself is a small, black plastic box, usually about 1 inch square, with either 4 or 5 pins on the bottom . Many Mitsubishi models use a 4-pin relay for the fuel pump circuit.

Mitsubishi Fuel Pump Relay Location by Model

Mitsubishi Montero (Pajero) – 4th Generation (2007-2019)

On the 4th generation Montero (also known as Pajero or Shogun), the fuel pump relay is located in the passenger compartment fuse box behind the dashboard, not in the engine bay . Specifically:

  • The fuse box is at the bottom of the dashboard behind a protective cover
  • Relay R4 is designated as "Fuel pump relay 1"
  • Relay R6 is designated as "Fuel pump relay 2"

This model uses two fuel pump relays, so if one fails, the other may still operate, but performance will be compromised. Check both relays if you suspect an issue.

Mitsubishi Montero – 2001 Model

For the 2001 Montero, the fuel pump relay is located under the hood in the fuse/relay box near the battery on the driver's side . The relay is typically labeled "FUEL PUMP" or "FP" on the relay box cover diagram. This is a standard 4-pin or 5-pin relay depending on the specific trim level .

Mitsubishi L200 (2006-2015)

The Mitsubishi L200 pickup truck has its fuel pump relay in the engine compartment fuse box on the left side near the battery . The relay is labeled as R4 – Fuel pump relay in the relay box . The main fuse box contains a dedicated 15A fuse for the fuel pump circuit as well, which is fuse number 16 .

Mitsubishi Space Wagon (1990s models)

For the Mitsubishi Space Wagon with the 4G63 engine, the fuel pump relay is not in the cabin fuse panel. Instead, it is located beside the computer box (ECU) . This is an 8-pin relay, and the fuel pump wire is colored black with a blue stripe . Check near the passenger side footwell or behind the glove box area for the ECU and relay.

Mitsubishi Grandis

The Mitsubishi Grandis fuel pump relay can be found in the fuse box under the dashboard on the driver's side . The low-pressure fuel pump is located inside the fuel tank, while the high-pressure pump is near the engine. The relay is part of the interior fuse panel.

Mitsubishi Diamante – 1992 Model

For the 1992 Mitsubishi Diamante, the fuel pump relay is called the Multiport Fuel Injection Relay and is located behind the glove box on the passenger side of the dashboard . This relay controls power to the fuel pump relay, so it functions similarly.

Mitsubishi Eclipse – 2006-2007 Model

The 2006 and 2007 Mitsubishi Eclipse has two fuel pump relays located in the fuse box under the driver's side dashboard . Additionally, the underhood fuse box contains fuse number 24 (15A) that powers the fuel pump circuit . If you're having fuel pump issues, check both the relays and this fuse.

Mitsubishi Outlander

For the Mitsubishi Outlander, the fuel pump relay is located in the engine compartment relay box . This box is on the right side of the engine bay, near the driver's side. The relay is typically labeled "FUEL PUMP" or "FP" on the diagram inside the cover .

How to Test a Mitsubishi Fuel Pump Relay

Before replacing the relay, you can test it to confirm it's faulty. Here's a simple method:

  1. Listen for the pump – Turn the ignition key to the "ON" position (don't start the engine). You should hear a 2-3 second whirring sound from the fuel tank area. If you don't hear anything, the relay or pump may be bad.
  2. Swap with a similar relay – If your fuse box has another relay with the same part number (like the horn or fog light relay), swap them. If the fuel pump starts working, the original relay was bad .
  3. Use a multimeter – Check for continuity between the relay terminals. With the relay unplugged, apply 12V to the coil terminals and listen for a click. If no click, the relay is defective.

Safety Precautions When Working with Fuel Pump Relays

Always take these precautions when working on your fuel system:

  • Turn off the vehicle and remove the key from the ignition before touching any electrical components
  • Disconnect the battery negative terminal before replacing the relay
  • Work in a well-ventilated area – fuel vapors are flammable
  • Use a flashlight – the relay box can be in shadowed areas

Why You Should Replace Your Fuel Pump with a Quality Aftermarket Part

If you've confirmed the relay is good but the fuel pump itself is failing, you need a reliable replacement. A failing fuel pump can destroy your engine in seconds by causing a lean condition. Investing in a quality pump from the start saves you money and headaches down the road.

KEMSO Fuel Pumps are the top choice for American drivers who demand reliability, performance, and value. KEMSO offers high-performance and OEM replacement fuel pumps that are designed to meet or exceed factory specifications. Here's why KEMSO stands out:

  • Lifetime warranty – Every KEMSO pump comes with a lifetime warranty, so you never have to buy another pump
  • High performance – KEMSO 340LPH pumps support up to 600 BHP, making them perfect for both daily drivers and high-horsepower builds
  • OEM replacement – Direct fit for most Mitsubishi models, including Montero, L200, Eclipse, and Outlander
  • Ethanol compatible – Viton-lined components resist ethanol degradation, essential for E15 and E85 fuels
  • USA-based support – Technical assistance from American technicians
  • Competitive pricing – Priced at $79.98 for most models, KEMSO pumps are 30-40% cheaper than many premium brands
  • Broad vehicle coverage – KEMSO offers 17 different models covering 98% of gasoline-powered cars and trucks made after 1995
  • Independent lab testing – KEMSO pumps maintain 98% efficiency even after 15,000 hours of continuous operation

Thousands of satisfied customers have made the switch. One LS1-swapped Jeep owner reported: "I've put 30,000 miles on my Jeep since installing the KEMSO pump. Zero hiccups, even at 12,000 feet where thinner air strains lesser pumps" . Another Subaru STI owner noted that the KEMSO 340LPH pump was a "straightforward, reliable upgrade that delivers consistent fuel pressure and flow" .

Whether you're replacing a failing OEM unit or upgrading for more power, KEMSO has the right fuel pump for your Mitsubishi. Visit their website to browse their full lineup and find the perfect fit for your vehicle: https://www.kemsoracing.com/

Final Thoughts

Finding the Mitsubishi fuel pump relay location is the first step in diagnosing a no-start or stalling issue. While the relay is usually in the engine compartment fuse box on most models, some vehicles like the Montero and Grandis have it under the dashboard. Always check your owner's manual or the diagram on the fuse box cover for exact placement.

If the relay checks out but the fuel pump is the problem, don't cut corners. A failed pump can cause serious engine damage. Choose a quality aftermarket pump like KEMSO that comes with a lifetime warranty and USA-based support. For the best selection of high-performance fuel pumps designed for Mitsubishi vehicles and other applications, visit https://www.kemsoracing.com/ to explore their complete lineup of OEM-replacement and performance fuel pumps backed by lifetime warranties and USA-based technical support.


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