Changing The Fuel Filter In A 1999 Lexus Rx300: Step-By-Step Guide

If you're looking to change the fuel filter on a 1999 Lexus RX300, you should know that it's located inside the fuel tank, and it's unlikely you'll need to change it. Lexus dealership mechanics report that they have never changed a fuel filter as a maintenance item, only when the fuel pump assembly is replaced. However, if you do need to change it, you can access the fuel tank by removing the rear seat.

How to change the fuel filter of a 1999 Lexus RX300

The fuel filter is part of the fuel pump assembly

The fuel filter in a 1999 Lexus RX300 is part of the fuel pump assembly and is located inside the fuel tank. It is not a maintenance item and does not need to be replaced unless there is an issue with contaminated fuel.

If you do need to change the fuel filter, you can access the fuel pump assembly through an access hole in the driver's side rear seat. However, it is a complicated process and is not recommended unless you have experience with car maintenance.

Some owners of the Lexus RX300 have never changed the fuel filter, even after many miles. One owner reported that their filter still looked brand new at 95,000 miles. Another owner with 148,000 miles on their car was advised that the filter only needed to be changed if the car had been using fuel from a third-world country or if there was another issue with the fuel.

If you are experiencing issues with your fuel system, such as reduced fuel efficiency or engine errors, it may be beneficial to use a fuel system cleaner before attempting to change the fuel filter.

It's located in the gas tank

To access the fuel filter in your 1999 Lexus RX300, you must first remove the rear seat. This will reveal an access hole to the fuel tank, where the fuel filter is located.

Jack up the car and locate the fuel filter in front of the fuel tank. To remove the old fuel filter, use a 5/8" wrench to disconnect one end, and simply detach the plastic clip on the other end. Be sure to have plenty of rags on hand, as fuel may leak from the tank once the filter is removed.

Once the old filter is out, installing the new one is a simple process. It is not necessary to change the fuel filter unless you are experiencing issues with contaminated fuel or the fuel pump.

You access it by removing the rear seat

To access the fuel filter on a 1999 Lexus RX300, you will need to remove the rear seat. This is because the fuel filter is located inside the fuel tank, and the access panel to the fuel pump is under the rear seat on the driver's side.

First, pry up the plastic covers over the seat floor bolts. Then, use a 14mm socket to remove the two seat floor bolts at the front. Release the seat dust flap so that you can lean the seat forward. Pull back the carpet in the cargo area. Using a flathead screwdriver, pry up the three black plastic retaining discs. Remove the 10mm bolt under the carpet trim that was held in place by the three discs. Then, remove the two 14mm bolts. Now you should be able to carefully remove the seat from the vehicle.

Once the seat is removed, you will have access to the fuel pump and fuel filter. The fuel pump is located under the trim pieces and seat belts, which can be removed with a 14mm socket. Be sure to disconnect the negative cable on the battery before beginning any work.

You may not need to change it unless the fuel is contaminated

The fuel filter in a 1999 Lexus RX300 is part of the fuel pump assembly and is located inside the fuel tank. It is designed to trap dirt, rust, scale and other impurities from entering the fuel pump, fuel injectors and engine without affecting fuel pressure.

You may not need to change the fuel filter unless the fuel is contaminated. In 11 years, one Lexus Master Certified mechanic has never changed a fuel filter as a maintenance item. The only time they replaced one was when they replaced the fuel pump assembly. Another Lexus owner with 148,000 miles on their car has never changed the filter.

However, if you are experiencing problems with your engine, it may be worth checking the condition of the fuel filter first, as it is an inexpensive and easy fix. Signs of a bad fuel filter include poor engine performance, misfire or rough idle, vehicle stalling, and fuel system component failure.

It can be a difficult process, so consider getting professional help

Changing the fuel filter on a 1999 Lexus RX300 can be a difficult process, so consider getting professional help. The fuel filter is located in the fuel tank, and while some people have found it to be a relatively simple procedure, others have described it as a "major PITA".

If you do decide to attempt the process yourself, here is a step-by-step guide based on information from online forums where car enthusiasts and mechanics have shared their experiences:

Firstly, you will need to remove the rear seat to access the fuel tank. This will give you an access hole to work with. Be aware that there is retained pressure in the fuel line, so take precautions to prevent fuel from splashing inside the vehicle compartment. You will also want to have plenty of rags on hand as there may be some leakage when you disconnect the fuel filter.

Next, you will need to disconnect the fuel pump and sender gauge connector, as well as the fuel tank main tube fuel tube connector from the fuel section plate. You will then need to remove the fuel pump and sender gauge assembly from the fuel tank by lifting it up and disconnecting the fuel sub-suction hose from the fuel return jet tube.

At this point, you can remove the fuel pressure regulator, fuel return jet tube assembly, and fuel suction filter. Be careful when handling these components as they are essential for your fuel system to function properly.

Now you can finally remove the fuel filter itself. Disconnect the fuel pump connector from the fuel pump and pull out the fuel filter assembly.

To install the new fuel filter, simply follow these steps in reverse. Make sure all connections are secure and that there are no leaks before starting your engine.

While it is possible to change the fuel filter on a 1999 Lexus RX300 yourself, it is important to note that some mechanics and Lexus enthusiasts have stated that they have never needed to change this filter during their years of experience. One mechanic specifically mentioned that in 11 years of working with Lexus, they had only replaced a fuel filter when it was changed along with the fuel pump assembly. Therefore, unless you are experiencing issues with your fuel system or have reason to believe the filter is contaminated, it may not be necessary to change it.

If you are unsure about any part of this process or simply don't feel comfortable attempting it yourself, it is always best to consult a professional mechanic who can ensure the job is done safely and correctly.

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