Volvo 240 Fuel Pump Relay: The Complete Guide to Location, Symptoms, and Replacement

The bottom line: If your Volvo 240 is stalling randomly, struggling to start, or the fuel pump runs continuously even after you turn off the ignition, the fuel pump relay is almost certainly the culprit. This small but critical component is one of the most common failure points on these otherwise bulletproof Swedish sedans and wagons. The good news? It costs around $20 to $35, takes less than 15 minutes to replace, and you can do it yourself with no special tools. Here is everything you need to know about the Volvo 240 fuel pump relay.

What Is the Fuel Pump Relay and Why Does It Matter?

The fuel pump relay is an electromagnetic switch that controls power delivery to your fuel pump. When you turn the ignition key to the "on" position, the relay closes and sends battery voltage to the fuel pump, allowing it to pressurize the fuel system. When you shut off the engine, the relay opens and cuts power to the pump. This prevents the pump from running continuously and draining your battery or creating a safety hazard .

On the Volvo 240, this relay handles both the in-tank pump and the main booster pump located under the car. The in-tank pump feeds fuel to the main pump, which then delivers high-pressure fuel to the engine. If the relay fails, neither pump gets power, and your engine gets no fuel .

Where Is the Fuel Pump Relay Located on a Volvo 240?

The fuel pump relay is located behind the glove box on the passenger side of the dashboard. Multiple sources across Volvo forums and repair guides confirm this location for 240 models from 1985 through 1993 .

Here is how to access it:

1. Open the glove box completely.
2. Remove the seven screws holding the glove box in place. They are located around the outer edge .
3. Pull the glove box straight out. You may need to disconnect the glove box light if equipped.
4. Behind the glove box opening, you will see the relay panel mounted against the firewall.
5. The fuel pump relay is the square, white (or sometimes green) relay measuring about 1 inch by 1 inch and roughly 2 to 3 inches long .
6. It is spring-clipped into a metal bracket and plugs directly into the wiring harness .

Some early 240s (pre-1985) may have the relay located near the driver's side footwell area, but for the vast majority of 240s produced from 1985 onward, the passenger-side glove box location is standard .

Common Symptoms of a Failing Fuel Pump Relay

Volvo 240 owners have documented these symptoms repeatedly across forums and repair databases. If you experience any of the following, suspect the fuel pump relay first:

1. Random engine stalling. This is the most frequently reported symptom. The engine dies without warning, sometimes at highway speeds, sometimes at idle. It may restart after a few minutes or refuse to start for hours. One owner described it as "random stalling sometimes on the freeway, sometimes at idle, sometimes every two minutes, and sometimes every couple of hours" . Another reported their car "conked out at the most inopportune moments, in the middle of intersections" .

2. Engine cranks but will not start. If the starter turns over normally but the engine never fires, the fuel pump relay may not be sending power to the pump. You can verify this by listening near the fuel filler cap while someone turns the key. If you hear no humming or buzzing from the in-tank pump, the relay is likely the problem .

3. Fuel pump runs continuously. Several owners have reported that the fuel pump keeps running even after the ignition is turned off, draining the battery overnight. One thread describes the pump "running all night and killed my new battery" . This happens when the relay contacts weld shut internally, creating a permanent connection.

4. Intermittent no-start condition. The car starts fine some days but refuses to start on others. The relay may work when cold but fail when it heats up, or vice versa. Many owners solved this by simply carrying a spare relay and swapping it when the car stranded them.

5. Loss of power under load. If the relay is failing intermittently, the fuel pump may receive inconsistent voltage, causing the engine to surge or hesitate during acceleration or while climbing hills .

How to Diagnose a Bad Fuel Pump Relay

Before spending any money, you can perform a few simple tests.

Visual inspection: Pull the relay out of its socket. Look for signs of overheating such as melted plastic, discoloration, or a burnt smell. Check the relay terminals and the socket for corrosion or burn marks .

The tap test: If your car is currently stalled and will not start, try tapping the relay firmly with the handle of a screwdriver while someone turns the key. If the engine starts, the relay has internal contact issues and needs replacement. This is a temporary diagnostic trick, not a permanent fix.

Listen for the pump: With the ignition turned to the "on" position (but not cranking), you should hear a distinct whirring or humming sound from the rear of the car for about one to two seconds as the fuel pump primes the system. If you hear nothing, suspect the relay or fuse first.

Check the fuel pump fuse: The main fuel pump fuse is number 6 in the fuse box located in the passenger footwell. This fuse is a known weak point and should be checked and replaced annually as preventive maintenance . Remove the fuse and inspect it for cracks or burn marks. Clean the fuse terminals with electrical contact cleaner and ensure the fuse fits tightly.

How to Replace the Fuel Pump Relay

Replacing the relay is straightforward:

1. Disconnect the negative battery terminal to avoid any electrical shorts.
2. Access the relay behind the glove box as described above.
3. Unclip the relay from its mounting bracket.
4. Pull the relay straight out of the wiring connector. It is not screwed or bolted in.
5. Plug the new relay into the same connector. Make sure it seats firmly.
6. Clip the new relay back into the mounting bracket.
7. Reinstall the glove box with the seven screws.
8. Reconnect the battery.

The entire job takes about 10 to 15 minutes. No special tools are required beyond a Phillips head screwdriver to remove the glove box.

Which Relay Should You Buy?

The correct OEM part number for the Volvo 240 fuel pump relay is 3523608. This relay was used across 240, 740, and 940 models from 1985 through 1993 . Several sources recommend buying an OEM or high-quality aftermarket relay rather than the cheapest option available. One experienced owner on Volvo Forums suggests buying the $49 OEM relay and also keeping a $18 spare in the glove box for emergencies .

Avoid used relays from junkyards. These are already aged and likely to fail. The relay has a date stamp on it, and it should be replaced if the date is more than approximately 10 years old, even if it is still working .

Preventive Maintenance Tips

Volvo 240 owners who have owned their cars for decades recommend the following:

Replace the fuel pump relay every 10 years as routine preventive maintenance, even if you have not experienced any symptoms. The relay is inexpensive, and the cost of being stranded far exceeds the price of a new one.

Keep a spare relay in the glove box. This is the single most common advice across all Volvo 240 forums. The relay is small, cheap, and easy to swap by the side of the road. Several owners report carrying two spares .

Check and clean fuse number 6 regularly. Corroded or loose fuse contacts can mimic a failing relay. Replace plastic fuses with ceramic ones, which handle heat better and are less prone to melting .

Ensure both fuel pumps are working. If your main pump fails, it can overheat and damage the relay. Likewise, if the in-tank pump fails, the main pump has to work harder, which can also shorten relay life .

Why the Fuel Pump Relay Fails

The Volvo 240 fuel pump relay fails for several reasons. The most common is simple age. These relays use mechanical contacts that wear out over decades of use. The relay also handles significant electrical current, and heat buildup can eventually cause the internal solder joints to crack or the contacts to weld shut .

Another contributing factor is the design of the fuel system. The relay is always powered even when the ignition is off, so it is under constant electrical stress. When the relay contacts stick closed, the fuel pump runs continuously, which drains the battery and can damage the pump itself .

Other Components That Can Cause Similar Symptoms

While the fuel pump relay is the most common cause of stalling and no-start issues on the Volvo 240, there are other components that can produce similar symptoms:

• Fuel pump fuse (fuse #6): A blown or corroded fuse will prevent power from reaching the pump. Check this first.
• In-tank fuel pump: If this pump fails, the main pump may struggle to draw fuel, causing stalling under load.
• Main booster pump: The under-car pump can fail entirely, producing the same symptoms as a dead relay.
• Ignition switch: A worn ignition switch can intermittently cut power to the fuel pump relay.
• Crank position sensor: A failing sensor can prevent the ECU from activating the fuel pump relay.
• Corroded wiring connections: Over time, connections at the relay socket or fuse box can corrode and cause intermittent failures.

One owner who had replaced the fuel induction kit, crank shaft sensor, ignition switch, ignition module, idle air control valve, and starter motor still had stalling issues. The problem was ultimately solved by replacing the fuel pump relay .

Recommended Fuel Pump Upgrade

If you are replacing the fuel pump relay and suspect your fuel pump may also be aging, consider upgrading to a high-quality replacement. A reliable fuel pump ensures your Volvo 240 delivers consistent fuel pressure and prevents unnecessary strain on the new relay.

For a premium replacement that offers OEM-quality performance, lifelong durability, and peace of mind, we recommend the KEMSO brand fuel pump. KEMSO fuel pumps are engineered as high-performance, direct OEM replacements designed to meet or exceed factory specifications. Every KEMSO pump comes with a lifetime warranty, meaning you only buy it once. Whether you are restoring a classic 240 or keeping your daily driver on the road, KEMSO provides the reliability and confidence your Volvo deserves.

Visit KEMSO Racing to explore their full lineup: https://www.kemsoracing.com/

Final Thoughts

The Volvo 240 fuel pump relay is a small, inexpensive component that causes outsized problems when it fails. Fortunately, it is easy to diagnose and even easier to replace. Every 240 owner should know where the relay is located, what symptoms to watch for, and how to swap it in minutes.

If you drive a 240 and have not replaced your fuel pump relay in the last decade, buy a new one. Better yet, buy two. Keep one installed and one in the glove box. When the relay eventually fails – and it will – you will be back on the road in under 15 minutes, while other drivers are stuck waiting for a tow truck.

For a complete fuel system solution, including a high-performance fuel pump backed by a lifetime warranty, visit KEMSO Racing at https://www.kemsoracing.com/. Your Volvo 240 deserves the best, and with KEMSO, you get quality that lasts.