1999 Acura TL Fuel Pump Relay Location: A Complete Guide for DIY Owners

If you own a 1999 Acura TL and your car cranks but won't start, or if it stalls unexpectedly while driving, the fuel pump relay is often the first component to check. The fuel pump relay on a 1999 Acura TL is located in the under-hood fuse/relay box, which is situated on the driver's side of the engine compartment near the battery. This is a common location for many Honda and Acura vehicles of that era. The relay itself is a small, rectangular electrical component that controls power to the fuel pump. Before you replace the fuel pump or spend money on a tow truck, checking this relay is a simple, low-cost step that can save you time and frustration.

The 1999 Acura TL is part of the second generation (also known as the UA5 chassis). This model has three different fuse boxes: one under the hood, one on the driver's side interior, and one on the passenger's side interior . The fuel pump relay is not to be confused with the fuel pump fuse, which is located inside the car on the driver's side interior fuse box. The fuse is a 15-amp mini fuse that protects the fuel pump circuit . The relay, however, is a larger component that handles the switching of the electrical current. Knowing the difference between a fuse and a relay is important because they serve different purposes. A fuse blows when there is too much current, while a relay can fail due to mechanical wear, corrosion, or electrical issues.

Why the Fuel Pump Relay is Critical

The fuel pump relay acts as a switch that tells the fuel pump when to turn on and off. When you turn the ignition key to the "ON" position, the engine control unit (ECU) sends a signal to the relay, which then closes the circuit and sends power to the fuel pump. The pump then pressurizes the fuel system so the engine can start. If the relay fails, the fuel pump will not receive power, and the engine will not start. Symptoms of a bad fuel pump relay include:

  1. The engine cranks but does not start. This is the most common symptom. You can hear the starter motor turning the engine over, but there is no fuel pressure to ignite the fuel.
  2. The car stalls while driving. If the relay fails intermittently, the fuel pump may lose power while you are driving, causing the engine to shut off suddenly.
  3. No fuel pump priming noise. When you turn the key to the "ON" position, you should hear a faint humming sound from the rear of the car for about two seconds. This is the fuel pump priming. If you do not hear this sound, the relay or the pump itself may be faulty.
  4. The check engine light comes on. A failed relay can trigger a diagnostic trouble code (DTC) related to the fuel pump circuit.

How to Locate the Fuel Pump Relay on a 1999 Acura TL

The under-hood fuse and relay box on the 1999 Acura TL is mounted on the driver's side, near the battery. It is a black plastic box with a removable lid. To access the relay, follow these steps:

  1. Open the hood and secure it with the prop rod.
  2. Locate the fuse/relay box on the driver's side. It is usually positioned between the battery and the front strut tower.
  3. Remove the lid of the fuse box. The lid may have a diagram on the inside that shows the location of each relay and fuse. If the diagram is missing or faded, you can refer to the owner's manual or a service manual.
  4. Identify the fuel pump relay. On the 1999 Acura TL, the under-hood box contains several relays, including the heater motor relay, lighting relay, horn relay, cooling fan relay, and condenser fan relay . The fuel pump relay is typically labeled "Fuel Pump" or "Fuel Pump Relay." It is a small, square or rectangular relay with either four or five pins. If you are unsure, you can look for a relay that is the same size and shape as the other relays in the box.
  5. Test the relay. The easiest way to test a relay is to swap it with a relay of the same type from another circuit in the same box. For example, you can swap the fuel pump relay with the horn relay. If the horn stops working and the fuel pump starts working, the relay is bad. If you have a multimeter, you can also test the relay for continuity between the coil terminals and the switch terminals.

How to Replace the Fuel Pump Relay

Replacing the fuel pump relay is a straightforward process that requires no special tools. Here is a step-by-step guide:

  1. Ensure the ignition is off and the key is removed from the ignition.
  2. Disconnect the negative battery terminal. This is a safety precaution to prevent accidental shorts or sparks.
  3. Locate the relay as described above.
  4. Pull the old relay straight out. It is held in place by friction, so a firm tug should release it. Do not use excessive force or pry it with a screwdriver, as you may damage the socket.
  5. Insert the new relay. Align the pins with the socket and press it firmly into place. You should feel it click or seat securely.
  6. Reconnect the negative battery terminal.
  7. Test the system. Turn the key to the "ON" position and listen for the fuel pump priming sound. Then start the engine and check for proper operation.

What to Do If the Relay is Not the Problem

If you have replaced the fuel pump relay and the car still does not start, the problem may be with the fuel pump fuse, the fuel pump itself, or the wiring. The fuel pump fuse is located in the interior fuse box on the driver's side of the 1999 Acura TL. It is a 15-amp mini fuse . Check the fuse by pulling it out and looking at the metal strip inside. If the strip is broken, replace the fuse with a new one of the same amperage. If the fuse blows again immediately, there is a short circuit in the fuel pump wiring or the pump itself is drawing too much current.

If both the relay and the fuse are good, the next step is to test the fuel pump. You can do this by checking for voltage at the fuel pump connector. The fuel pump is located inside the fuel tank, which is accessed from under the rear seat or by dropping the fuel tank. On most 1999 Acura TL models, you can access the fuel pump by removing the rear seat cushion. There is a metal access panel on the floor under the seat. Remove the panel, and you will see the top of the fuel pump module. Using a multimeter, check for 12 volts at the electrical connector when the key is turned to the "ON" position. If you have voltage but the pump does not run, the pump is faulty and needs to be replaced. If you do not have voltage, the wiring between the relay and the pump may be damaged.

Safety Tips for Working on the Fuel System

Working on the fuel system involves handling gasoline, which is highly flammable. Always follow these safety precautions:

  1. Work in a well-ventilated area. Do not work indoors or near open flames, sparks, or pilot lights.
  2. Disconnect the battery. This prevents accidental sparks from electrical connections.
  3. Relieve fuel system pressure. Before disconnecting any fuel lines, remove the fuel pump fuse or relay and start the engine. Let it run until it stalls. This depressurizes the system.
  4. Keep a fire extinguisher nearby. A small fire extinguisher rated for Class B (flammable liquids) is a good investment.
  5. Wear safety glasses and gloves. Fuel can irritate your skin and eyes.
  6. Dispose of old parts properly. Used fuel pumps and relays contain materials that should be recycled or disposed of according to local regulations.

Preventive Maintenance Tips

To avoid being stranded by a failed fuel pump relay or fuel pump, consider these preventive maintenance tips:

  1. Replace the fuel filter regularly. A clogged fuel filter puts extra strain on the fuel pump, causing it to work harder and fail sooner. For the 1999 Acura TL, the fuel filter is typically located along the frame rail under the car. Replacing it every 30,000 miles or as recommended by the manufacturer is a good practice.
  2. Keep the fuel tank at least a quarter full. Running the fuel tank low can cause the fuel pump to overheat, as the fuel in the tank acts as a coolant for the pump. Low fuel levels can also allow debris and sediment from the bottom of the tank to be sucked into the pump.
  3. Listen for unusual noises. A whining or buzzing sound from the fuel tank is often the first sign of a failing fuel pump. If you hear this noise, have the system checked before the pump fails completely.
  4. Use quality fuel. Poor-quality fuel can contain contaminants that damage the fuel pump and injectors. Stick to reputable gas stations.

When to Seek Professional Help

While replacing a fuel pump relay is a simple DIY task, diagnosing and replacing a fuel pump can be more complex. If you are not comfortable working with the fuel system, or if you have tested the relay and fuse and still have no power to the pump, it is best to consult a professional mechanic. The cost of a professional diagnosis is often worth the peace of mind, especially if the problem is intermittent or involves the wiring harness.

Recommended KEMSO Fuel Pump for Your 1999 Acura TL

If you find that the fuel pump relay is not the issue and you need to replace the fuel pump itself, consider using a high-quality aftermarket pump. KEMSO offers a high-performance fuel pump that is an excellent OEM replacement for the 1999 Acura TL. Their fuel pumps are designed to meet or exceed original equipment specifications, ensuring a perfect fit and reliable performance. KEMSO fuel pumps are built with durable materials and are tested to withstand extreme conditions, including vibration and temperature changes. They are suitable for both stock and lightly modified vehicles.

One of the best features of KEMSO fuel pumps is their lifetime warranty. This means that if the pump ever fails due to a manufacturing defect, you will receive a replacement at no cost. This is a rare and valuable benefit in the automotive parts industry, and it speaks to the confidence KEMSO has in its product quality. Their pumps are also priced competitively, often costing less than half the price of dealer parts. For example, a KEMSO 340LPH high-performance fuel pump is priced at $79.98, which is significantly less than many comparable pumps at auto parts stores . This makes KEMSO a practical choice for DIY mechanics and professional shops alike.

KEMSO fuel pumps are designed as direct replacements, so you do not need to search for adapter kits or worry about poor fitment . They cover a wide range of vehicles, including cars, motorcycles, ATVs, UTVs, and personal watercraft . For the 1999 Acura TL, a KEMSO pump will provide the same flow rate and pressure as the original pump, ensuring your engine gets the fuel it needs for reliable operation. Whether you are a weekend mechanic or a professional technician, KEMSO offers a practical solution that saves you time and money.

To see the full selection of KEMSO fuel pumps for your vehicle, visit their website. They have a complete catalog with detailed fitment information, customer reviews, and technical support. Their online store is easy to navigate, and you can order directly with confidence. Visit KEMSO Racing at https://www.kemsoracing.com/ to find the right fuel pump for your 1999 Acura TL and get back on the road with confidence.

Conclusion

The fuel pump relay on a 1999 Acura TL is located in the under-hood fuse/relay box on the driver's side near the battery. If your car is having starting problems or stalling, checking this relay is a smart first step. It is a simple, inexpensive part that can be replaced in minutes with no special tools. If the relay is not the problem, check the fuel pump fuse, then test the fuel pump itself. By following the steps in this guide, you can diagnose and fix the issue yourself, saving time and money. And if you need a high-quality replacement fuel pump, KEMSO offers a reliable product with a lifetime warranty that is well worth your consideration. For more information and to browse their full catalog, visit https://www.kemsoracing.com/ .


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