Replacing The Fuel Pressure Regulator In Your Bmw 325I E90

The fuel pressure regulator is part of the fuel pump assembly, which is located in the right side of the fuel tank. To replace the fuel pressure regulator, you will need to remove the rear seat cushion to access the fuel pump assembly. You will then need to disconnect the electrical connectors and fuel lines from the fuel pump assembly before unscrewing the threaded collar and lifting the fuel pump assembly out of the fuel tank. Be sure to replace the fuel pump assembly sealing O-ring before installing the new fuel pump assembly. Finally, reconnect the fuel lines and electrical connectors, fill the fuel tank, and check for leaks.

Disconnecting the electrical connector

Step 1: Remove the rear seat cushion by pulling up on the corner to detach the locking tabs. This will give you access to the fuel pump module, which is located on the right side of the fuel tank.

Step 2: Peel back the carpet from the rear seat cushion area to expose the access panel. This will make it easier to reach the electrical connector.

Step 3: Using a 10mm socket or a suitable tool, remove the four nuts that secure the access panel. Be careful not to drop them into the fuel tank.

Step 4: Lift and remove the access panel lid. Make sure you move it out of the way so you can easily access the electrical connector on the fuel pump module.

Step 5: Disconnect the electrical connector by squeezing the release tabs and pulling it off. This will allow you to access the fuel pump and begin the replacement process.

It is important to work in a well-ventilated area and take the necessary safety precautions when performing this task, as fuel and fuel vapors are highly combustible. Always refer to a trusted repair manual or seek professional assistance if you are unsure about any steps.

Disconnecting the fuel line

Step 1: Park your car on a level surface and engage the parking brake. It is important to work on a level surface to ensure stability and prevent any accidental spills.

Step 2: Remove the fuel cap to relieve the pressure in the fuel system. This will make it safer to work on the fuel line and reduce the risk of fuel spraying out.

Step 3: Locate the fuel line. On the BMW 325i E90, the fuel line is typically located on the driver's side of the vehicle, near the rear of the engine bay. It is usually a flexible rubber hose that connects the fuel tank to the engine.

Step 4: Place a drip pan or a container under the fuel line to catch any fuel that may spill during the disconnection process. Fuel can be flammable and hazardous, so it is important to take the necessary precautions.

Step 5: Loosen the clamp that secures the fuel line to the fuel tank or engine. You may need to use a wrench or a pair of pliers to loosen the clamp. Be careful not to damage the fuel line or the surrounding components.

Step 6: Gently pull the fuel line away from the fuel tank or engine. You may need to wiggle it a bit to loosen it, but be careful not to kink or damage the fuel line.

Step 7: Once the fuel line is disconnected, carefully inspect it for any signs of damage, cracks, or leaks. If the fuel line is damaged, it is important to replace it with a new one to ensure the safety and proper functioning of your vehicle.

Step 8: If you are replacing the fuel line, install the new fuel line by reversing the above steps. Ensure that the new fuel line is securely clamped and that there are no leaks before starting the vehicle.

It is important to work carefully and safely when disconnecting the fuel line, as fuel can be hazardous. Always refer to your vehicle's service manual for specific instructions and safety precautions.

Removing the fuel pump module

Step 1: Disconnect the Battery

Before beginning any work on your vehicle, it is important to disconnect the negative battery terminal to prevent any accidental electrical shorts. This will ensure your safety and protect the vehicle's electrical system.

Step 2: Drain the Fuel Tank

It is recommended to drain the fuel tank before removing the fuel pump module. Run the vehicle for about 20 seconds to equalize the fuel level in the siphon unit. Then, use an anti-static siphon hose to drain the fuel from the tank into a suitable storage container. You can monitor the fuel level via the fuel level sender units and a digital volt/ohm meter to ensure a safe and complete drainage.

Step 3: Access the Fuel Pump

The fuel pump is located on the right side of the fuel tank. To access it, you will need to remove the rear seat cushion by grabbing the corner and pulling it up to detach the locking tabs. Once the seat is removed, peel back the carpet on the right side of the rear seat area to expose the access panel.

Step 4: Remove the Access Panel

Using a socket set, remove the four 10mm nuts that secure the access panel. Lift the access panel lid and move it out of the way to access the electrical connector on the fuel pump module.

Step 5: Disconnect the Electrical Connectors

Disconnect the fuel pump electrical connectors by squeezing the release tabs and pulling them off. Be careful not to damage the connectors or the fuel pump module.

Step 6: Remove the Fuel Lines

To remove the fuel lines from the fuel pump, press the retaining tab towards the line and hold it in place while sliding the line off the fuel pump module. Be gentle and cautious to avoid damaging the hoses or the module.

Step 7: Remove the Fuel Pump Module Collar

The fuel pump module is secured in place with a threaded collar. To remove it, you can use a BMW special tool (number 16 1 022) or a brass punch and a rubber mallet. Tap the threaded collar counter-clockwise to loosen it, and then unscrew it the rest of the way by hand. If the collar is damaged during this process, it will need to be replaced with a new part.

Step 8: Lift the Fuel Pump Module

With the collar removed, slowly lift the fuel pump module out of the tank. Be careful when handling the module as fuel may still be present. Use a cloth to catch any dripping fuel, and immediately place the module in a bucket to minimize fuel spillage.

Step 9: Reinstall the New Fuel Pump Module

When installing the new fuel pump module, ensure that the O-ring is properly seated on the fuel tank. Hand-tighten the threaded collar, and then use the BMW special tool or a brass punch and rubber mallet to tighten it securely. Reconnect the fuel lines and electrical connectors, and reassemble the interior of the vehicle.

Step 10: Fill the Fuel Tank and Test

Before attempting to start the vehicle, fill the fuel tank with about 2 gallons of fuel. Once the fuel pump is operating normally, fill the remainder of the tank and check for any leaks.

Removing the old fuel pump

Step 1: Prepare the Car

Before beginning the removal process, make sure you have the necessary tools and parts, including a new fuel pump and sealing O-ring. Park your car on level ground and engage the parking brake. Disconnect the negative battery cable to prevent any accidental electrical shorts.

Step 2: Drain the Fuel Tank

Run the vehicle for about 20 seconds to equalize the fuel level in the siphon unit. Then, remove the fuel cap and insert an anti-static siphon hose down the fuel filler neck. Pump out the fuel from the tank into a suitable storage container. You can monitor the fuel level using a digital volt/ohm meter (DVOM) and a wiring diagram to measure the resistance across the fuel level sender units as the fuel level drops.

Step 3: Access the Fuel Pump

The fuel pump is located on the right side of the fuel tank. To access it, you will need to remove the rear seat cushion by grabbing the corner and pulling it up to detach the locking tabs. Once the seat is removed, peel back the carpet from the right side rear seat cushion area of the body.

Step 4: Disconnect the Fuel Pump Electrical Connectors

Remove the four 10mm nuts from the access panel and lift it away. You will now be able to access the electrical connector on the fuel pump module. Disconnect the fuel pump electrical connectors by squeezing the release tabs and pulling them off.

Step 5: Remove the Fuel Lines

To remove the fuel lines, press the retaining tab towards the line and hold it in place while sliding the line off the fuel pump module. Be careful not to damage the hose or fuel pump module. There are multiple fuel lines that need to be disconnected, so make sure you release the correct tab for each line.

Step 6: Remove the Fuel Pump Module

The next step is to unscrew the fuel pump module threaded collar. This can be done using a BMW special tool (number 16 1 022) or a brass punch and a rubber mallet. Tap the threaded collar counter-clockwise to loosen it, and then unscrew the rest of the way by hand. If the collar is damaged during this process, you will need to replace it with a new part.

Step 7: Lift Out the Fuel Pump Module

With the collar removed, slowly lift the fuel pump module out of the tank. Be careful when handling the fuel lines, as they can be difficult to remove. Wrap a piece of mechanic's wire around the two black hoses at the bottom of the fuel pump module to make it easier to reinstall them later. Once all the fuel lines are removed, lift the fuel pump module out of the fuel tank and place it in a bucket or plastic bin to catch any dripping fuel.

Step 8: Install the New Fuel Pump

Before installing the new fuel pump, make sure to replace the fuel pump assembly sealing O-ring. Ensure that the O-ring is properly installed on the fuel tank before placing the new fuel pump into the tank. Attach the lower fuel lines to the fuel pump module, making sure that all lines are securely connected. Align the tab with the fuel tank and press the fuel pump module into place. Hand-tighten the threaded collar, and then use the BMW special tool or a brass punch and rubber mallet to tighten it securely.

Step 9: Reconnect the Fuel Lines and Electrical Connectors

Reconnect the external fuel lines and electrical connectors. Fill the fuel tank with about 2 gallons of fuel before attempting to start the car. Once the fuel pump is operating normally, fill the remainder of the fuel tank and check for any leaks.

This step-by-step guide should help you successfully remove the old fuel pump from your BMW 325i E90. Remember to work in a well-ventilated area and take the necessary safety precautions when handling fuel.

Installing the new fuel pump

First, you will need to drain your fuel tank. Run the vehicle for about 20 seconds to equalize the amount of fuel in the siphon unit. Next, disconnect the negative battery cable. Then, remove the fuel cap and 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.

Now, you can access the fuel pump, which is located on the right side of the fuel tank. Working in the rear of the vehicle interior, grab the corner of the rear seat cushion and pull it up to detach the locking tabs. Peel the carpet away from the right side rear seat cushion area of the body. Remove the four 10mm nuts from the access panel and lift the panel away.

Disconnect the fuel pump electrical connectors by squeezing the release tabs and pulling them off. Next, remove the lines at the fuel pump by pressing the retaining tab and sliding the line off the module. Be careful not to damage the hose or fuel pump module.

Now, you need to unscrew the fuel pump module threaded collar. There is a BMW special tool for this, but if you don't have it, you can use a brass punch and a rubber mallet. Tap the threaded collar on one of the ridges counter-clockwise to loosen it, then unscrew the rest of the way by hand. If the collar is damaged during this process, you will need to replace it.

Remove the collar from the fuel tank and set it aside. Now, lift the fuel pump module up slightly out of the tank and remove the large fuel line by pressing the retaining tab and sliding the line off. Be careful as this one can be tough to get off.

With the large upper fuel line removed, remove the top of the fuel pump module and set it aside. Working inside the fuel tank, wrap a piece of mechanic's wire around the two black hoses at the bottom of the module and pull them out, laying them aside. Press the retaining tab on the fuel line and remove it from the module.

With all the fuel lines removed, lift the fuel pump module up and out of the fuel tank. Catch any dripping fuel with a cloth and immediately place the module in a bucket to minimize fuel spillage.

When installing the new fuel pump, be sure to replace the fuel pump assembly sealing O-ring. Ensure the O-ring is properly installed on the fuel tank before installing the new fuel pump. Attach the lower fuel lines to the new module, slide it into the fuel tank, and connect the upper large fuel line.

Align the tab with the fuel tank and press the new fuel pump module into the tank. Hand-tighten the threaded collar, then use the BMW special tool or tap it tight with a brass punch and rubber mallet. Connect the external fuel lines and electrical connectors, then reassemble the interior.

Finally, fill the fuel tank with about 2 gallons of fuel before attempting to start the car. Once the new fuel pump is operating normally, fill the remainder of the tank and check for leaks.

Frequently asked questions