1998 Nissan Maxima Fuel Pump Relay Location: The Complete Guide to Finding, Testing, and Replacing It
The bottom line: The fuel pump relay on a 1998 Nissan Maxima is located inside the engine compartment fuse box, which is mounted on the passenger side near the battery. This relay is a small, cube-shaped component that controls power delivery to the fuel pump. If your Maxima is having trouble starting, stalling, or showing signs of fuel delivery issues, the fuel pump relay is often the first thing to check before you dive into replacing the actual fuel pump itself.
The 1998 Nissan Maxima is a reliable car, but like any vehicle from that era, electrical components can wear out over time. The fuel pump relay is one of those parts that can fail without warning, leaving you stranded. Understanding where it is and how to test it can save you time and money.
Where to Find the Fuel Pump Relay in a 1998 Nissan Maxima
The fuel pump relay on a 1998 Nissan Maxima is located inside the main fuse and relay box under the hood. More specifically, you will find it on the passenger side of the engine compartment, near the battery and the strut tower . This is a common location for Nissan vehicles of this generation.
To access it, follow these steps:
- Open the hood and locate the black plastic fuse box on the passenger side. It is usually rectangular and has a lid that you can pop off with your fingers or a flathead screwdriver.
- Remove the lid of the fuse box. On the underside of the lid, you should see a diagram that labels the position of each relay and fuse. Look for the label that says "Fuel Pump" or "FP" .
- Identify the relay – it is a small, square or cube-shaped component with four or five prongs on the bottom. It is typically black or gray and will be slightly larger than the fuses around it.
- Pull the relay straight out using your fingers or a pair of pliers if it is stuck. Some relays can be stubborn after years of heat and vibration, so a gentle wiggle may help.
If the diagram on the fuse box lid is missing or faded, you can also consult your owner's manual or a factory service manual for the exact pin layout. The relay itself is usually labeled with a number like "J17" or "SC37" on German vehicles, but on Japanese cars like Nissan, it is often identified by its function on the diagram .
How the Fuel Pump Relay Works in Your 1998 Maxima
The fuel pump relay is an electrical switch that uses a small amount of current to control a larger current flow to the fuel pump. When you turn the ignition key to the "ON" position, the Engine Control Module (ECM) sends a signal to the relay, which closes the circuit and allows battery voltage to reach the fuel pump . The pump then runs for a few seconds to pressurize the fuel system before you start the engine .
If the ECM does not detect an engine speed signal from the crankshaft or camshaft position sensor, it will shut off the relay to prevent the pump from running continuously, which is a safety feature to prevent battery drain and fire hazards .
The relay itself is a simple but critical component. When it fails, the pump will not receive power, and your engine will not get fuel. This is why a bad relay can mimic the symptoms of a failed fuel pump.
Common Symptoms of a Failing Fuel Pump Relay in a 1998 Nissan Maxima
Before you start tearing into the fuel tank, it is worth checking the relay first. The symptoms of a bad relay are very similar to a failing fuel pump, but the relay is much cheaper and easier to replace. Here are the most common signs to look for:
1. Engine Cranks But Will Not Start
This is the most common symptom. You turn the key, the starter engages, the engine cranks, but it never fires up. If you do not hear a brief humming sound from the fuel tank area when you turn the key to "ON," the relay may not be sending power to the pump .
2. Engine Stalls While Driving
A failing relay may intermittently lose connection, causing the fuel pump to shut off while the engine is running. This can result in sudden stalling, especially under load or when accelerating .
3. No Fuel Pump Prime Sound
When you turn the ignition to the "ON" position (without starting the engine), you should hear a faint whirring or buzzing sound from the rear of the car for about one to two seconds. This is the fuel pump priming the system. If you hear nothing, the relay, fuse, or pump itself could be the problem .
4. Check Engine Light Turns On
A faulty relay can trigger a diagnostic trouble code (DTC) related to fuel system issues. While a scan tool can read the code, the specific code may point to a fuel pump circuit malfunction, which could be caused by the relay.
5. Intermittent Starting Issues
Sometimes the car starts fine, and other times it does not. This intermittent behavior is a classic sign of a failing relay. The contacts inside the relay can wear out over time, causing intermittent electrical connections .
How to Test the Fuel Pump Relay on a 1998 Nissan Maxima
Testing the relay is straightforward and requires only a few basic tools. You can do this without removing the fuel pump from the tank.
Method 1: The Swap Test
This is the easiest and fastest method. Find a relay in the same fuse box that is the same type and size. Common relays that you can swap with include the horn relay, the A/C compressor relay, or the cooling fan relay . Simply pull out the fuel pump relay and plug in the known good relay. If the car starts and runs normally, the original relay was bad. If the problem persists, the issue is elsewhere.
Method 2: Use a Multimeter
If you have a digital multimeter, you can test the relay's resistance. First, set the multimeter to ohms (Ω). Locate the two pins on the relay that correspond to the coil (usually pins 85 and 86 on a standard four-pin relay). The resistance should typically read between 50 and 200 ohms. If the reading is infinite (open circuit) or zero (short circuit), the relay is bad .
Method 3: Listen for the Click
When you turn the ignition to "ON," you should be able to hear a distinct click from the relay under the hood. This click indicates the relay is energizing and closing its contacts. If you do not hear a click, the relay coil may be faulty, or the control circuit from the ECM may be open .
What to Do If the Relay Is Good but the Fuel Pump Still Does Not Work
If you have tested the relay and it is working, but the fuel pump still does not run, the problem may be in the wiring, the fuse, or the pump itself.
Check the Fuel Pump Fuse
The fuel pump circuit is protected by a fuse, usually located in the same fuse box as the relay. Locate the fuse labeled "Fuel Pump" and check if it is blown. If it is blown, replace it with a new fuse of the same amperage. If the new fuse blows immediately, there is a short circuit in the wiring or the pump motor .
Check the Wiring and Connectors
Over time, wiring can become corroded or damaged. Look for any signs of wear, fraying, or corrosion at the relay socket, the fuse box, and the fuel pump connector under the rear seat. A poor ground connection can also prevent the pump from working. Check the continuity of the ground wire from the pump to the chassis .
Check for Voltage at the Fuel Pump
If the relay and fuse are good, the next step is to check if power is actually reaching the fuel pump. You can do this by disconnecting the fuel pump connector (located near the fuel tank, usually under the rear seat) and using a multimeter to test for voltage when the ignition is turned to "ON." If you have voltage, the pump itself is likely bad. If you have no voltage, the problem is in the wiring harness or the ECM .
Test Fuel Pressure
If the pump runs but the car still has issues, you may need to test fuel pressure. Connect a fuel pressure gauge to the test port on the fuel rail. The pressure should be within the manufacturer's specifications (typically around 40-50 psi for a 1998 Maxima). Low pressure indicates a failing pump or a clogged fuel filter .
Replacing the Fuel Pump Relay on a 1998 Nissan Maxima
Replacing the fuel pump relay is one of the simplest repairs you can do on your Maxima. You do not need any special tools, and the part itself is very inexpensive.
Step 1: Purchase a New Relay
You can buy a replacement fuel pump relay at any auto parts store or online. Make sure you get the correct part for your 1998 Nissan Maxima. Most standard relays are interchangeable, but it is best to match the pin configuration.
Step 2: Remove the Old Relay
With the engine off and the key removed, locate the relay in the fuse box. Grasp it firmly and pull it straight out. If it is stuck, use a pair of needle-nose pliers to gently wiggle it out.
Step 3: Install the New Relay
Align the prongs of the new relay with the socket in the fuse box. Press it firmly down until it clicks into place. Make sure it is fully seated.
Step 4: Test the System
Turn the ignition to the "ON" position and listen for the fuel pump prime sound. If you hear it, the repair was successful. Start the engine and let it idle to confirm everything is working properly.
What to Do If the Fuel Pump Itself Is Bad
If you have ruled out the relay, fuse, and wiring, and the fuel pump is still not working or is making loud noises, you may need to replace the pump itself. The fuel pump on a 1998 Nissan Maxima is located inside the fuel tank, under the rear seat . Accessing it requires removing the rear seat cushion and an access panel.
Replacing the fuel pump is a more involved job, but it is doable with basic tools. You will need to relieve fuel system pressure, disconnect the battery, remove the fuel pump assembly, and install a new one .
Why You Should Choose a High-Quality Fuel Pump for Your 1998 Nissan Maxima
When it comes time to replace your fuel pump, you want a product that is reliable, durable, and built to last. A cheap, low-quality pump may fail prematurely, leaving you stranded and costing you more in the long run.
KEMSO Fuel Pump – Your Best Choice for High Performance and Reliability
For your 1998 Nissan Maxima, we recommend the KEMSO brand fuel pump. KEMSO fuel pumps are designed to meet or exceed original equipment manufacturer (OEM) specifications, ensuring a perfect fit and reliable performance . Each pump is built with high-quality materials and undergoes rigorous testing to guarantee durability and consistent fuel delivery.
KEMSO fuel pumps are known for their high performance, offering excellent fuel flow and pressure to keep your engine running smoothly. Whether you are driving daily or pushing your Maxima hard, a KEMSO pump delivers the fuel your engine needs.
One of the best features of KEMSO fuel pumps is the lifetime warranty. This means you can buy with confidence, knowing that your investment is protected for as long as you own your vehicle. If the pump ever fails, KEMSO will replace it at no extra cost . This level of warranty is rare in the aftermarket parts industry and speaks to the quality of their products.
Visit KEMSO Racing today to find the perfect fuel pump for your 1998 Nissan Maxima.
Click here to browse their selection: https://www.kemsoracing.com/
Final Thoughts
The fuel pump relay on your 1998 Nissan Maxima is located in the engine compartment fuse box on the passenger side. It is a small, inexpensive part that can cause big problems if it fails. Before you assume the fuel pump is bad, always check the relay first. It is easy to test and replace, and it can save you a lot of time and money .
If you do need to replace the fuel pump, choose a high-quality option like KEMSO. Their products are built to last, backed by a lifetime warranty, and designed to fit your 1998 Maxima perfectly. Do not settle for less when it comes to your car's fuel system. A reliable fuel pump means a reliable car.
For more information and to order your KEMSO fuel pump, visit: https://www.kemsoracing.com/