Replacing Fuel Filter In E350 Mercedes: Step-By-Step Guide

Replacing the fuel filter on a Mercedes E350 is a complex task that requires specific tools and a good understanding of car mechanics. The fuel filter is located underneath the car, inside a protective box on the right side, underneath the rear passenger seat. Before starting, it is important to turn off the ignition and lift the car to access the filter. The filter is then removed by unscrewing it from its bracket and unclamping the fuel hoses. To install the new filter, simply reverse the process, ensuring that all components are properly tightened and secured.

The fuel filter plays a crucial role in the fuel injection system of a Mercedes-Benz E-Class, purifying the fuel before it reaches the engine block. A clean fuel filter ensures optimal engine performance, while a dirty or clogged filter can lead to poor engine performance and hard-starting problems. Therefore, it is recommended to replace the fuel filter as part of regular maintenance or when fuel contamination or system repairs are performed.

The cost of replacing the fuel filter on a Mercedes E350 can vary depending on location, with estimates ranging from $165 to $290. It is worth noting that this task can be performed by intermediate DIYers, but it requires careful handling due to the potential fire hazard associated with fuel leaks.

Locate the fuel filter

To locate the fuel filter on your Mercedes-Benz E350, you'll need to first turn off the ignition and remove the key. This is important as you don't want the fuel ignition system to turn on while you're working.

Next, you'll need to lift the car and secure it with jack stands on level ground. This is because the fuel filter is located underneath the car, specifically on the right side underneath the rear passenger seat.

Once the car is lifted, you'll find the fuel filter inside a protective box underneath the rear passenger seat. Use a ratchet wrench, extension, and 10mm socket to remove the box cover.

It's important to work in a well-ventilated area when locating and replacing the fuel filter, as the task may expose you to fuel leaks or vapors.

Remove the old fuel filter

To remove the old fuel filter from your Mercedes-Benz E350, follow these steps:

Firstly, ensure the ignition is off and the key has been removed from the switch. This is important as you don't want the fuel ignition system to turn on while you're working. Next, you'll need to lift the car and secure it with jack stands on level ground. This is necessary as the fuel filter is located underneath the car.

Now, locate the fuel filter. In the E350, it is inside a protective box on the right side underneath the rear passenger seat. Once you've found it, use a ratchet wrench, extension, and 10mm socket to carefully remove the box cover. With the fuel filter exposed, use a screwdriver to remove the hose clamps that are attached to the fuel hoses. Be sure to have a drip pan nearby, as some fuel will spill out of the lines and filter.

At this point, you can unscrew the old fuel filter from its bracket. Be cautious, as you don't want to spill excess fuel. With the old filter removed, you're now ready to install the new one.

Remember to wear protective gear and work in a well-ventilated area when performing this task, as it may expose you to fuel leaks or vapors.

Prepare the new fuel filter

To prepare the new fuel filter for your Mercedes-Benz E350, you will need to purchase the correct replacement part. The fuel filter is typically located underneath the car, on the right side, inside a protective box underneath the rear passenger seat.

First, it is important to consult your vehicle's maintenance schedule to ensure you are replacing the fuel filter at the recommended interval. For the E350, this is generally every 40,000 to 80,000 miles.

Next, gather the necessary tools and safety equipment. You will need a ratchet wrench, an extension, and a 10mm socket to remove the protective box cover. A flathead screwdriver will also be required to remove the hose clamps attaching the fuel filter to the fuel hoses. It is recommended to have a drip pan nearby to catch any fuel that spills out of the lines and filter during the process. Work in a well-ventilated area and keep a fire extinguisher nearby as fuel is highly combustible.

Now, you can proceed to purchase the correct replacement fuel filter for your Mercedes-Benz E350. Ensure that the new fuel filter is made to original equipment specifications and is of OEM quality or better. This will ensure that it effectively traps contaminants and prevents them from entering the fuel system.

Before beginning the installation, it is crucial to turn off the ignition and completely remove the key from the switch. This will ensure that the fuel ignition system is not accidentally activated during the process.

Additionally, as the fuel filter is located underneath the car, you will need to lift the vehicle and secure it with jack stands on level ground. This will provide access to the work area.

Once you have prepared the new fuel filter, gathered the necessary tools and safety equipment, and followed the preliminary steps, you can proceed to install the new fuel filter by following the reverse steps of the removal process.

Install the new fuel filter

Now that the old filter has been removed, you can grab the new fuel filter and mount it on its bracket. The filter should be positioned with the arrow facing the front of the engine. Tighten the filter casing to the frame rail using a flathead screwdriver.

Once the filter is mounted, you can position the fuel lines back in place. If your E-Class has reusable hose clamps, install them now. If not, use the new clamps that you purchased or that came with the new filter.

Once everything is in place and properly tightened, bolt the protective box cover back on.

Finally, check the fuel system for leaks while the engine is running.

Check for leaks

Once you have finished installing the new fuel filter, you will need to check for leaks.

First, fill the fuel tank with about two gallons of fuel. Then, before attempting to start the engine, check that the fuel pump is operating normally. Once you are satisfied that it is, fill the rest of the fuel tank and check for leaks.

If there is a leak, it will need to be repaired before driving the car. Leaks at the fuel filter connections may also require new O-rings in the push-on connections to the fuel filter.

Frequently asked questions