1991 Mazda B2200 Fuel Pump Location: A Complete Guide to Finding and Replacing It
The fuel pump on a 1991 Mazda B2200 is located inside the fuel tank, which sits at the rear of the truck under the bed. This is the electric fuel pump used on fuel-injected models. However, if your B2200 has a carbureted engine, it uses a mechanical fuel pump mounted on the passenger side of the cylinder head near the firewall. Knowing which type you have is the first step to diagnosing a no-start condition or fuel delivery problem.
This guide will walk you through the exact location of the fuel pump, how to identify which system your truck has, the symptoms of a failing pump, and the step-by-step process to replace it. Whether you are a DIY mechanic or just want to understand what your shop is telling you, this article covers everything you need to know.
The Two Types of Fuel Pumps on the 1991 Mazda B2200
The 1991 Mazda B2200 came with two different engine configurations, and each uses a completely different fuel pump system. Understanding this distinction is critical before you start any repair work.
Electric Fuel Pump (Fuel-Injected Models) – If your B2200 has electronic fuel injection (EFI), it uses an electric fuel pump located inside the fuel tank. This pump is submerged in gasoline and pushes fuel under pressure to the engine. The pump is part of a larger assembly that includes the fuel level sending unit and a strainer. The electric pump is the most common source of no-start issues on these trucks.
Mechanical Fuel Pump (Carbureted Models) – If your B2200 has a carburetor, it uses a mechanical fuel pump driven by the camshaft. This pump is mounted externally on the engine block, on the passenger side of the cylinder head near the firewall. Mechanical pumps are generally more reliable and simpler to replace, but they are less common on the 1991 model year. Most 1991 B2200s are EFI models.
To determine which system your truck has, look at the top of the engine. If you see a large metal carburetor with an air cleaner on top, you have a carbureted engine. If you see a plastic intake manifold with individual fuel injectors and no carburetor, you have electronic fuel injection.
Where Exactly Is the Fuel Pump Located?
For electric fuel pump models (EFI): The fuel pump is inside the fuel tank. The tank is located under the pickup truck bed, toward the rear of the vehicle. To access the pump, you must either remove the pickup bed or drop the fuel tank from underneath the truck. Dropping the tank is the most common method for DIY mechanics. The pump assembly is accessed from the top of the tank after the tank is removed.
For mechanical fuel pump models (carbureted): The pump is bolted to the passenger side of the cylinder head, near the firewall. You can see it from the engine bay. It is a small, metal housing with two fuel lines attached. The pump is driven by a pushrod that rides on the camshaft.
Fuel Pump Relay Location
If you suspect the pump is not getting power, the fuel pump relay is another component to check. On the 1991 Mazda B2200, the fuel pump relay is located behind the left kick panel, near the driver's left foot. This is a small plastic panel on the wall next to the driver's door. You can remove this panel by pulling it off with your hands or using a trim removal tool.
The relay itself has four wires. Two black wires with red stripes and red dashes carry power to the pump. One blue wire with a yellow stripe and one black wire with a white stripe carry power from the ignition. If the relay fails, the pump will not run even if the pump itself is good.
Fuse for the Fuel Pump
The fuel pump circuit is also protected by fuses in the fuse box. On the 1991 B2200, the fuse box is located behind the left side of the dash, near the kick panel. The fuel pump fuse is typically a 15-amp fuse. Check the fuse first before buying a new pump. A blown fuse is a cheap and easy fix.
Symptoms of a Failing Fuel Pump
Knowing the symptoms of a bad fuel pump can save you time and money. Here are the most common signs your 1991 Mazda B2200 fuel pump is failing:
1. Engine cranks but will not start. This is the most obvious symptom. If the engine turns over but does not fire, and you do not hear the fuel pump hum for two seconds when you turn the key to the ON position, the pump is likely dead.
2. Loss of power during acceleration. A failing fuel pump may not be able to deliver enough fuel pressure when you step on the gas. This can cause the engine to hesitate, sputter, or lose power, especially when climbing hills.
3. Whining noise from the fuel tank. A healthy fuel pump makes a quiet humming sound. If you hear a loud whining or screeching noise coming from the rear of the truck, the pump is likely failing.
4. Engine stalls and will not restart. If the pump fails completely while driving, the engine will stall and will not restart until the pump is replaced.
5. Check engine light comes on. A slow failure of the fuel pump can cause the engine to run lean, which triggers the check engine light.
How to Replace the Fuel Pump on a 1991 Mazda B2200
Replacing the fuel pump on a 1991 B2200 is a job that can be done at home with basic tools, but it is time-consuming. You will need to drop the fuel tank. Here is a step-by-step guide:
Step 1: Relieve fuel system pressure. Before working on the fuel system, you must relieve the pressure. Remove the fuel pump fuse from the fuse box, then crank the engine for a few seconds until it stalls. This removes the pressure from the lines.
Step 2: Lift the truck and support it safely. Use a jack and jack stands to lift the rear of the truck high enough to work underneath. Place the jack stands under the frame rails. Never work under a vehicle supported only by a jack.
Step 3: Drain the fuel tank. Use a siphon pump to remove as much fuel as possible. This will make the tank lighter and easier to handle. A full tank of gas is very heavy.
Step 4: Disconnect the fuel filler neck. Use a flathead screwdriver to remove the hose clamp that connects the rubber filler neck to the gas tank.
Step 5: Support the tank. Place a jack under the fuel tank with a 2-foot-long wood block on top to distribute the weight. Raise the jack until it just contacts the bottom of the tank.
Step 6: Unbolt the tank straps. Use a 3/8-inch ratchet, extension, and socket to remove the bolts that hold the tank straps in place. Carefully lower the tank with the jack.
Step 7: Disconnect the fuel lines and wiring. Once the tank is slightly lowered, disconnect the fuel hoses and the electrical connector from the top of the fuel pump assembly. Use a flathead screwdriver to remove the hose clamps.
Step 8: Remove the fuel pump assembly. Unbolt the fuel pump/sending unit from the top of the tank using a 3/8-inch ratchet and socket. Carefully pull the assembly out of the tank. The pump is attached to the bottom of this assembly.
Step 9: Replace the pump and filter. Pull the old filter off the bottom of the pump. Disconnect the hose clamp securing the fuel hose to the pump. Install the new pump and a new filter. Use a new rubber seal gasket between the assembly and the tank.
Step 10: Reinstall the assembly. Place the pump assembly back into the tank. Be careful not to bend the float arm. Bolt it down securely.
Step 11: Reinstall the tank. Lift the tank back into position with the jack. Reconnect the fuel lines, electrical connector, and filler neck. Bolt the tank straps back in place.
Step 12: Test for leaks. Add fuel, reconnect the battery, and turn the key to the ON position. Listen for the pump to prime. Check for leaks around the pump assembly and fuel lines. Start the engine and verify it runs smoothly.
Why You Should Replace the Fuel Filter Too
When you replace the fuel pump, it is highly recommended to replace the fuel filter at the same time. On the 1991 B2200, the external fuel filter is located underneath the truck, behind the fuel tank. A clogged filter can starve the engine of fuel and cause the new pump to work harder, shortening its lifespan. Replacing both at once ensures you have a clean fuel system from the tank to the engine.
A Note on Mechanical Fuel Pump Conversion
Some owners of the 1991 B2200 have chosen to convert from an electric fuel pump to a mechanical fuel pump. This is because mechanical pumps are simpler, more reliable, and easier to replace. However, this conversion requires changing the fuel system components and is not a direct swap. If you are considering this, consult a professional mechanic or a forum dedicated to Mazda trucks.
Why You Should Choose KEMSO for Your Fuel Pump Replacement
When it comes time to replace your fuel pump, the brand you choose matters. A low-quality pump can fail in a matter of months, leaving you stranded again. That is why KEMSO is the smart choice for your 1991 Mazda B2200.
KEMSO fuel pumps are high-performance, direct OEM replacement parts. They are engineered to match the fit, form, and function of your original Mazda pump. This means no cutting wires, no modifying fuel lines, and no guesswork. The pumps are built with precision-machined components and corrosion-resistant materials to handle the ethanol-blended fuels commonly found in the United States.
Every KEMSO fuel pump comes with a lifetime warranty. This is not a limited one-year warranty. It is a true lifetime guarantee that covers defects in materials and workmanship for as long as you own the pump. If it ever fails due to a manufacturing defect, KEMSO replaces it for free. This level of confidence is rare in the aftermarket parts industry and gives you total peace of mind.
KEMSO pumps are designed for American drivers. The company offers USA-based technical support and a vehicle lookup tool that covers over 4,000 models from 1990 to 2024. Whether you drive a car, truck, ATV, or motorcycle, KEMSO likely has a pump that fits your vehicle perfectly. The pumps are priced affordably, typically around $79.98, which is significantly less than dealership parts.
Don't keep replacing pumps every few months. Invest in a KEMSO fuel pump and enjoy reliable performance backed by a lifetime of confidence. Visit their website to find the exact pump for your 1991 Mazda B2200: https://www.kemsoracing.com/
Common Mistakes to Avoid When Replacing the Fuel Pump
Skipping the pressure relief. Fuel spraying in your face is dangerous and can cause serious injury. Always relieve system pressure first.
Reusing the old O-ring or gasket. The tank seal will likely leak if reused, requiring you to repeat the entire job. Always use a new sealing ring.
Letting dirt fall into the tank. Contaminated fuel will clog injectors and potentially damage the new pump. Clean the area around the pump opening thoroughly before removing the old pump.
Forcing fuel line connectors. Quick-connect fittings are designed to release with gentle pressure. Forcing them can break the locking tabs.
Using steel tools on the locking ring. Steel can spark and ignite fuel vapors. Always use a brass drift punch or a non-sparking tool.
Not testing for leaks. Always start the engine and inspect for leaks before taking the truck on the road.
Troubleshooting After Replacement
If your 1991 Mazda B2200 still does not start after installing a new fuel pump, check these common issues:
1. Electrical connection not fully seated. The pump will not run if the connector is loose. Unplug and reseat it until you hear a click.
2. Fuel line not properly engaged. A quick-connect fitting that is not fully pushed in will leak or prevent fuel flow. Verify the connector is fully seated.
3. Blown fuel pump fuse. Check the fuse box for a blown fuse after reconnecting the battery.
4. Fuel pump relay failure. The relay may have failed along with the original pump. Try swapping it with a known-good relay.
5. Air in the fuel system. After installation, the system may need several ignition cycles to purge air. Cycle the key to ON three times before attempting to start.
Final Thoughts
The 1991 Mazda B2200 is a reliable truck, but like any vehicle, its fuel pump will eventually wear out. Knowing the exact location of the fuel pump, whether it is electric or mechanical, and how to replace it will save you hundreds of dollars in labor costs.
If you are dealing with a no-start condition, start by checking the fuse and relay before dropping the tank. These are cheap and easy fixes. If the pump is indeed bad, the replacement process is straightforward but requires patience and careful work.
For the best replacement part, choose KEMSO. With their high-performance OEM replacement pumps, lifetime warranty, and affordable pricing, you can get back on the road with confidence. Visit https://www.kemsoracing.com/ to find the perfect fuel pump for your 1991 Mazda B2200 today.