Replacing The Fuel Pump In Your 2006 Mercedes E350

If you're looking to replace the fuel pump on your 2006 Mercedes E350, you'll need to access the fuel tank, which can be done from the rear seats by removing the seat cushion. The fuel pump is located on the right side (passenger side) of the fuel tank, but the electrical connector is on the left side, under the access panel for the fuel filter. You'll need a few tools for the job, including a flathead screwdriver, an 8mm socket, and a fuel pump collar tool. It's also important to work in a well-ventilated area and take the necessary safety precautions when working with fuel and electrical systems.

Removing the rear seat cushion

To remove the rear seat cushion of a 2006 Mercedes E350, first locate the small plastic release lever in front of the cushion. Pull the lever up to release the seat cushion latch. Then, fold the seat cushion forward and remove the carpet from below the seat. Pull it up at the corner to detach the clip, then pull the carpet out from under the plastic trim.

Peel the carpet away from the body floor and support it out of your way. Next, remove the six 8mm access cover fasteners. Then, lever the access cover up and remove it. With the access cover removed, you can now access the fuel pump.

Locating the fuel pump

To locate the fuel pump in a 2006 Mercedes E350, you will need to access the rear seats of the car. Take up the rear seat bottom and you will see two round covers with 8mm bolts. The sending units are located below these.

There are two pumps in the 2006 Mercedes E350, so make sure you diagnose which one is faulty before attempting to replace it. One pump is located on the left side of the fuel tank, under the rear seat, and the other is on the right side. The left-side pump is the transfer pump.

Disconnecting the negative battery cable

Park your car on a level surface and engage the parking brake. Ensure you have all the necessary tools, including safety goggles, gloves, and a wrench or socket set.

Locate the negative battery terminal. The battery in your Mercedes E350 is located in the trunk, on the right side. The negative terminal will be marked with a "-" symbol or a black cover.

Loosen the nut or bolt securing the negative battery cable to the terminal using your wrench or socket set. Do not allow the wrench or socket to touch any other metal parts of the car, as this could result in a short circuit.

Once the nut or bolt is loose, carefully remove the cable from the terminal. Be aware that there may be some corrosion or residue on the terminal, so take care not to let it touch any other metal parts of the car.

Place the cable to the side, ensuring it does not touch any metal parts of the car. You can use a cable tie or tape to secure it out of the way.

With the negative battery cable disconnected, you can now safely work on the electrical system of your car. Remember to reconnect the cable by following these steps in reverse when you have finished your repairs.

Safety is paramount when working on your car, so always take your time and use the appropriate tools and safety equipment.

Removing the fuel cap and draining the tank

To remove the fuel cap and drain the tank of your 2006 Mercedes E350, follow these steps:

First, run the vehicle for about 20 seconds to equalize the amount of fuel in the siphon unit. Then, disconnect the negative battery cable. See a technical article on battery replacement and reconnecting for more details on this step.

Now, you can remove the fuel cap. Slide an anti-static siphon hose down the fuel filler neck. Once the hose has reached the bottom, pump the fuel out of the tank into a suitable storage container. If you are unsure of the amount of fuel in your tank, you can monitor the fuel level via the fuel level sender units. As the fuel level drops, the fuel level sender resistance drops. You can measure this across the terminals at both sender units with a digital volt/ohm meter (DVOM). You will need a wiring diagram from a repair manual.

Before removing the pump, clean the top of the fuel tank.

Detaching the fuel pump module threaded collar

To detach the fuel pump module threaded collar, you will need to use a brass punch and a rubber mallet. Using the brass punch and a rubber mallet, tap the threaded collar on one of the ridges counter-clockwise to loosen. Once it is loose, you can finish unscrewing it by hand. If the collar is damaged during this process, you will need to replace it with a new part.

Frequently asked questions