Bmw E90 Fuel Pump: How Long Does It Last?

The fuel pump is a simple and rugged part of the fuel system. It is usually found inside the fuel tank and is responsible for sending fuel from the tank to the engine. Fuel pumps are built to be tough and there is really no reason to preemptively replace the fuel pump before 100,000 miles. In fact, fuel pumps have been known to last for over 200,000 miles in some cases.

The fuel pump on a BMW E90 can be replaced without removing the fuel tank. A faulty fuel pump can cause poor engine performance and hard starting problems. When they fail completely, you may be left with an engine that doesn't start.

The fuel pump is located on the right side of the fuel tank. To replace it, you will need a Phillips & flathead screwdriver, a socket set, and a new fuel pump and fuel pump sealing O-ring.

How to test if the E90 high-pressure fuel pump is faulty

If you suspect your E90's high-pressure fuel pump is faulty, you can perform the following tests to confirm:

• Check the fuel pump electrical connector and terminals under the rear seat cushion, below an access panel.
• Confirm the fuel pump is receiving the correct voltage when commanded on by the fuel pump control module using a digital volt-ohm meter (DVOM).
• If the correct voltage is present but the pump does not activate, it is likely faulty.
• Use the DVOM in conjunction with a wiring diagram to determine the correct terminals for testing.
• On E90 models, a fuel pump control module is used in place of the fuel pump relay.
• The fuel pump module can be activated for testing using a BMW scan tool. If you don't have access to one, attempting to start the vehicle will also activate the module.
• Check the fuel pressure and volume.
• Check the fuel pump current.

How to replace the E90 high-pressure fuel pump

To replace the E90 high-pressure fuel pump, you will need to drain the fuel tank and disconnect the negative battery cable. Then, remove the rear seat cushion and access the fuel pump electrical connectors and lines. Disconnect the lines and remove the threaded collar. Lift the fuel pump module out of the tank and replace it with a new one. Reinstall the fuel lines, electrical connectors, and rear seat cushion. Finally, fill the fuel tank and check for leaks.

How to prevent the E90 high-pressure fuel pump from failing

To prevent the E90 high-pressure fuel pump from failing, you should:

• Keep the fuel tank at least a quarter full. Gas acts as a coolant for the fuel pump, and if the tank runs dry, there is no liquid to cool the pump.
• Avoid driving with less than a quarter of a tank of gas. The weight of the fuel helps move it out of the tank, and with less fuel, there is less pressure pushing it through the fuel pump, meaning there is more effort taken by the pump.
• Keep the fuel system maintained. Parts in the fuel system are meant to function for a long time if maintained correctly. With regular inspections and fuel filter replacements, the parts will last as long as the manufacturer intends.
• Make sure the gas cap has a good seal, otherwise, fuel vapour can get out, and dust and debris can get in.
• Avoid poorly maintained gas stations. If there is water in the gas or corrosion on the nozzles, this can cause damage to the fuel system and shorten the life of the fuel pump.

How to know if the E90 high-pressure fuel pump is about to fail

The fuel pump is a simple and rugged part of the fuel system. It is usually found inside the fuel tank and is responsible for sending fuel from the tank to the engine. A faulty fuel pump can cause poor engine performance and hard starting problems. When they fail completely, you may be left with an engine that doesn't start. Here are some ways to know if your E90 high-pressure fuel pump is about to fail:

• Check the fuel pressure: A faulty fuel pump can cause low fuel pressure, which can result in hard starting or engine performance issues.
• Listen for unusual noises: If you hear unusual noises coming from the fuel pump, such as whining or grinding sounds, it may be failing.
• Fuel gauge issues: If your fuel gauge is reading incorrectly or not at all, it could be a sign that the fuel pump is failing.
• Engine misfires or stalls: If your engine is misfiring or stalling, it could be due to a failing fuel pump not supplying enough fuel to the engine.
• Fuel leaks: If you notice fuel leaks around the fuel pump or fuel lines, it could be a sign that the pump is failing and needs to be replaced.
• Increased fuel consumption: If you notice a sudden increase in fuel consumption, it could be a sign that the fuel pump is working harder to maintain fuel pressure, indicating a possible failure.
• Vehicle surging or hesitating: If your vehicle surges or hesitates while driving, it could be due to an inconsistent fuel supply from a failing fuel pump.
• Check Engine Light: If the Check Engine Light comes on and you notice a decrease in fuel efficiency, it could be a sign that the fuel pump is failing.
• Strange noises while driving: If you hear strange noises, such as whining or grinding sounds, while driving, it could be a sign that the fuel pump bearings are failing.
• Vehicle not starting: If your vehicle is not starting at all, it could be due to a failed fuel pump that is unable to deliver fuel to the engine.

How much does it cost to replace the E90 high-pressure fuel pump?

The cost of replacing the E90 high-pressure fuel pump varies depending on the dealership and the parts used. The cost of the parts alone can range from $500 to $900, while the labour costs can add a few hundred dollars more to the total cost. Some dealerships may charge up to $2,000 for the entire replacement, which includes both parts and labour.

It is worth noting that the cost of replacing the E90 high-pressure fuel pump can also depend on the year and model of the car, as well as the specific engine type. Some BMW models with the N54 or N55 turbocharged engine may require additional parts to be replaced along with the fuel pump, which can increase the overall cost of the replacement.

Furthermore, it is generally recommended to replace other components such as the intake manifold gaskets and throttle body gasket when replacing the high-pressure fuel pump, as these parts are prone to failure if reused. Additionally, it is advised to only use genuine BMW parts for the replacement to ensure reliability and avoid future issues.

Overall, the cost of replacing the E90 high-pressure fuel pump can range from a few hundred to a few thousand dollars, depending on the specific car model, the dealership, and the parts used.

Frequently asked questions