Replacing The Fuel Pump In A 1990 Toyota Corolla: Step-By-Step Guide

The fuel pump is an essential part of your car's fuel system, and while OEM fuel pumps can last a long time, they will eventually wear out. If your 1990 Toyota Corolla is experiencing issues with its fuel pump, you can save time and money by replacing it yourself. The fuel pump is located in the fuel tank, which is beneath the rear seats. To replace it, you will need a screwdriver (Philips and flat head), cloth, protective gloves, and of course, a replacement fuel pump. The process involves removing the rear seat base, disconnecting the wiring plug and connectors, starting the engine and letting it run until the car stalls, disconnecting the negative battery terminal, and carefully removing and replacing the old pump.

Removing the rear seat cushion

First, you will need to gather the necessary tools for the job. For this task, you will need a socket wrench, screwdrivers (both Phillips and flat head), and possibly a pry bar or trim removal tools. Have some gloves and safety goggles ready as well, to ensure your safety during the process.

Start by opening the rear doors of your Corolla. You will see two Phillips screws on the bottom edge of the rear seat back trim panel. Remove these screws and set them aside, being careful not to misplace them. Gently pull the trim panel forward and disengage it from the clips holding it in place. You may need to use a pry bar or trim removal tool to carefully pry the panel forward, starting from the bottom and working your way up the sides. Once the panel is removed, set it aside in a safe place.

Now, you should be able to see the fuel pump access cover. Before proceeding, take note of the wiring harness connected to the trim panel. You will need to carefully disconnect this harness before completely removing the panel. Once the harness is disconnected, set the panel aside. With the trim panel removed, you will have access to the rear seat cushion. There will typically be a metal bar running along the front edge of the seat cushion. This bar is held in place by a few screws or bolts, which you will need to remove. Again, make sure to keep track of the removed screws to make reassembly easier.

Once the bar is removed, you can start lifting the rear seat cushion up and out of the vehicle. It may be a tight fit, so work slowly and carefully to avoid damaging any surrounding components or the seat itself. Additionally, be cautious of the fuel pump wiring and any other components that may be attached to the seat frame, ensuring that you don't put excessive strain on these connections during removal. Once the seat cushion is completely removed, you will have full access to the fuel pump assembly and can proceed with replacing it.

Locating the fuel pump

Some fuel pumps can be accessible through the top of the gas tank (trap door) or only the float for the gas gauge. If you cannot locate the pump this way, you will need to remove the fuel tank from the vehicle. This is not a simple DIY repair, so it is recommended to seek the help of an experienced mechanic.

• Remove the gas filler cap to start reducing air pressure in the fuel system.
• Remove the rear seat base. You can do this by feeling along the edges of the seat to find and unhook the fastener clips that secure it in place.
• Remove the fuel pump service hole cover, which will look like a metal cover plate screwed into the bodywork.
• Disconnect any wiring plugs and connectors running into the fuel pump.
• Start the engine and let it run until the car stalls. This will release any excess fuel pressure from the system.
• Disconnect the negative battery terminal from the battery, which is located under the hood.
• Unscrew the circular plastic lid that holds the old pump in place. Be sure to remove any dirt or contaminants from the area first.
• Gently lift out the old fuel pump.

At this point, you will have successfully located and accessed the fuel pump, and you can proceed to install the new one. Remember that replacing a fuel pump can be a complex task, and it is always recommended to seek professional assistance if you are unsure about any part of the process.

Disconnecting the wiring

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Before beginning any work on your Toyota Corolla, it is essential to ensure your safety. Put on protective gloves to safeguard your hands from any dirt or sharp edges. Locate the fuel pump, which is situated within the fuel tank, beneath the rear seats. To access the fuel pump, you will need to remove the rear seat base. Start by feeling along the edges of the seat to find the fastener clips that secure it in place. Unhook these clips carefully.

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Once the rear seat base is removed, you will expose the fuel pump service hole. It is covered by a metal cover plate screwed into the bodywork. Unscrew and remove this cover plate to reveal the fuel pump. Now, you can begin the process of disconnecting the wiring. First, locate the wiring plug and any connectors running into the fuel pump. These are the components that you will need to disconnect.

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Before disconnecting the wiring, it is important to relieve the fuel system of excess pressure. To do this, start the engine and let it run until the car stalls. This procedure ensures that you can work on the fuel pump safely without the risk of excess fuel pressure. Once the engine has stalled, you can proceed to the next step. Remember to always exercise caution when working with any fuel-related components.

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Now, you can disconnect the wiring. Start by locating the negative battery terminal, which is usually found under the hood. Disconnect the negative terminal from the battery. This step is crucial to ensure that no power is supplied to the fuel pump during the replacement process. It is a safety measure to protect you from electrical hazards. Once the negative battery terminal is disconnected, you can proceed to the next step in the fuel pump replacement process.

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With the negative battery terminal disconnected, you have ensured that there is no power being supplied to the fuel pump. Now, you can safely disconnect the wiring plug and any connectors attached to the fuel pump. Take your time and be gentle during this process to avoid damaging any wires or connectors. Ensure that all wiring and connectors are properly disconnected before moving on to the next step in replacing the fuel pump in your 1990 Toyota Corolla.

Removing the old fuel pump

To remove the old fuel pump from your 1990 Toyota Corolla, first remove the gas filler cap to start reducing air pressure in the fuel system. Then, remove the rear seat base. You can do this by feeling along the edges of the seat to find the fastener clips that secure them, and unhooking them.

Next, remove the fuel pump service hole cover. This will look like a metal cover plate screwed into the bodywork. Disconnect the wiring plug and any connectors running into the fuel pump. Now, start the engine and let it run until the car stalls. This will remove any excess fuel pressure from the system.

Disconnect the negative battery terminal from the battery, which is located under the hood. Unscrew the circular plastic lid that holds the old pump in place, but be sure to remove any dirt from the area first to prevent contamination.

Finally, gently lift out the old fuel pump.

Installing the new fuel pump

To install the new fuel pump in your 1990 Toyota Corolla, you will need a screwdriver (both Philips and flat head), cloth, protective gloves, and, of course, a replacement fuel pump.

First, remove the rear seat base. Feel along the edges of the seat to locate and unhook the fastener clips that secure the seat. Next, remove the fuel pump service hole cover. This will look like a metal cover plate screwed into the bodywork.

Then, disconnect the wiring plug and any other connectors running into the fuel pump. Start the engine and let it run until the car stalls to relieve any excess fuel pressure from the fuel system.

Now, disconnect the negative battery terminal from the battery (located under the hood). Unscrew the circular plastic lid that holds the old pump in place, taking care to remove any dirt from the area first to prevent contamination.

Gently lift out the old fuel pump and remove and replace the old gasket around the access hole. Gently lower the new fuel pump into place and reconnect the wiring and cables.

Finally, replace the fuel pump service cover and rear bench seat. Reconnect the negative battery terminal and tighten the gas cap. Turn on the ignition for around 10-15 seconds to allow the new fuel pump to prime itself. You may need to repeat this a few times until the system is pressurised and the car will start.

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