Fuel Pump Failure: How Quickly Can It Happen?

High-pressure fuel pumps are crucial for ensuring a smooth and consistent engine operation. However, these pumps can malfunction or fail due to various factors, and the consequences can range from decreased fuel efficiency to a complete engine shutdown. Understanding the symptoms of a failing fuel pump is essential for vehicle owners to take timely action and prevent further damage. Some common signs of a failing high-pressure fuel pump include unusual noises from the fuel tank, engine struggling to start, power loss, poor fuel efficiency, and engine misfires. Addressing these issues promptly is crucial for maintaining vehicle performance, longevity, and on-road safety.

Lack of maintenance

To prevent this issue, it is crucial to use engine oil that meets OE specifications. Volkswagen, GM, and other OEMs have oil standards that address wear issues on the camshaft and pump follower. By using engine oil that meets these standards, you can help prevent premature wear and ensure the optimal performance of your high-pressure fuel pump.

In addition to oil changes, regular maintenance of the fuel pump and the entire fuel system is essential. This includes regular inspections, cleaning, and timely replacements of worn-out parts. Fuel system cleaning, in particular, is crucial for maintaining efficiency and performance. Over time, carbon deposits and other residues can build up in the fuel system, leading to reduced power, poor fuel economy, and potential engine damage. Therefore, it is recommended to perform fuel system cleaning every 15,000 miles or as needed, depending on the configuration of your injectors.

Furthermore, keeping your fuel level above half and regularly changing the fuel filter can also help prevent fuel pump problems. Contaminated fuel, which can include dirt, debris, or water, can damage the pump over time by increasing friction and causing premature wear. By maintaining adequate fuel levels and regularly changing the fuel filter, you can reduce the risk of contamination and prolong the lifespan of your fuel pump.

In summary, lack of maintenance, including insufficient oil changes, fuel system cleaning, and failure to address contamination, can lead to high-pressure fuel pump failure. By prioritizing regular maintenance and using the correct engine oil, you can help prevent premature wear and ensure the optimal performance of your vehicle's fuel pump.

Faulty sensors

The information generated by these sensors makes for the best possible combustion event, but these additional sensors can throw you a diagnostic curveball compared to older port fuel-injected systems. These sensors have a ±2% accuracy rate. If the sensors are malfunctioning, they can influence fuel trims. If a sensor fails or generates readings outside of set parameters, the system will go into a low-pressure safe mode to prevent damage to the system.

Faulty fuel rail pressure sensor symptoms include the following:

• Check Engine Light Turns On: The check engine light comes on if the ECM algorithms detect any sensor input that is known to be out-of-range. A bad fuel pressure sensor will disrupt the fuel supply, which prevents the engine from getting the gasoline it needs. This can lead to hard starts, no starts, loss of power, etc.
• Engine Start Problems: When you start your car, the PCM orders the fuel delivery system to surge a batch of fuel to the engine. Common rail systems like electronic diesels and GDI systems will have a low-pressure fuel pump that feeds approximately 80 psi to the high-pressure pump inlet.
• Poor Engine Performance: Your car’s engine may be producing less power than it should, which could indicate a problem with the fuel rail pressure sensor. The fuel rail pressure sensor is the feedback input that the ECM uses to determine how much pressure is in the rail. High engine load requires more fuel volume and pressure. The ECM must very accurately deliver the right amount of pressure if the engine is to perform as it should.
• Engine Misfires and Runs Rough: Problems will arise when an erratic fuel rail pressure sensor provides the wrong information to the PCM. Whether too much or too little fuel gets added to the mixture, nothing good comes out of the incorrect air-fuel mixture.
• Bad Fuel Mileage: When your fuel pressure sensor doesn’t work as it should, you’ll notice a considerable reduction in fuel economy and mileage.

Contaminated fuel

To prevent fuel pump failure due to contaminated fuel, regular fuel filter changes are essential. This simple practice can prevent contaminants from entering the pump, preserving its efficiency. Additionally, keeping fuel levels above half is crucial, as the fuel acts as a coolant for the pump during operation, preventing potential overheating and damage.

Using clean, uncontaminated fuel is another way to safeguard the pump from unnecessary wear and tear. Regular inspections and maintenance checks can also help identify and resolve potential issues, ensuring a longer lifespan and smoother performance from your fuel pump.

The fuel pump is responsible for delivering fuel from the tank to the engine, and contaminated fuel can compromise this function. By taking proactive measures, vehicle owners can ensure their fuel pumps' longevity and optimal performance.

Electrical issues

The fuel pump is responsible for delivering fuel to the engine, making it one of the most critical components in both petrol and diesel engines. When the fuel pump fails, the engine will not receive the necessary fuel to function, resulting in the vehicle not running at all. Therefore, it is essential to be aware of the signs of electrical issues with the fuel pump to prevent sudden vehicle failure.

Some symptoms of electrical issues with the high-pressure fuel pump include difficulty starting the car, engine stuttering or stalling at high speeds, and a decrease in fuel efficiency. Additionally, a whining noise from the fuel tank may indicate that the pump is close to permanent failure. If you experience any of these issues, it is recommended to consult a professional technician as soon as possible to diagnose and address the problem.

To test for electrical issues with the fuel pump, you can use a vehicle diagnostic tool, such as an OBD2 scanner, to read the error memory. Some specific fault codes related to the fuel pump include P0251 (fuel injection pump fuel metering control), P0230 (malfunction of the fuel pump primary circuit, such as low voltage), P0148 (fuel supply error), and P0627 (fuel pump "A" control circuit open).

It is worth noting that regular maintenance, such as fuel filter changes and avoiding frequent low fuel levels, can help prevent electrical issues and other common causes of fuel pump failure. By prioritising the health of your vehicle's fuel pump, you can ensure its longevity and maintain optimal vehicle performance.

Overheating

An old and worn pump motor can also get too hot, which can, in turn, overheat the entire engine. This can cause the vehicle to stall, especially at high temperatures. In addition, if the engine is already operating at high temperatures, the fuel pump may overheat due to a clogged fuel filter, low fuel pressure, or inadequate lubrication.

To prevent overheating, it is important to maintain fuel levels above half, as this ensures that oil can reach the fuel pump. Regular fuel filter changes can also prevent overheating by keeping the fuel uncontaminated and preventing damage to the pump.

Frequently asked questions