HOW DOES A FUEL SYSTEM WORK?
In order for your vehicle’s engine to run smoothly, it needs to be provided with the proper ratio of fuel to air. A fuel injector is an electronically controlled valve that supplies fuel from the fuel pump to the vehicle’s engine. The fuel injector is capable of opening and closing multiple times a second. When the injector is activated, an electromagnet moves a plunger that opens the valve, allowing pressurized fuel to squirt out through a tiny nozzle. The nozzle is designed to make the fuel as fine a mist as possible so that it can burn easily. The fuel injector is controlled by the vehicle’s engine control unit, or ECU.
HOW DO I KNOW IF MY VEHICLE NEEDS A FUEL SYSTEM REPAIR?
Whether you drive a BMW, Mini or Audi, the signs of a faulty fuel system including a bad fuel pump or damaged or dirty fuel injector, are the same. A faulty fuel pump can cause difficulty starting and engine sputtering, while a faulty fuel injector will mess up the intervals in which fuel is sprayed or will prevent fuel from being sprayed into the engine altogether. In either instance your fuel system will need to be inspected.
The following are some symptoms of a faulty fuel pump:
Whining noise from the fuel tank.
If you hear a screeching or whining noise coming from the fuel tank while the car is running, there may not be enough fuel, a damaged pump, or a contaminant in the system.
Difficulty starting.
Because fuel pumps constantly run whenever the ignition is turned on, they can eventually wear out and weaken over time. A weak fuel pump may still pump fuel, but the vehicle may experience difficulty starting from the lack of pressure. A weakened fuel pump can cause the vehicle to take more cranks to start than normal, and in more serious cases may even cause the vehicle to require multiple turns of the key before it will start.
Engine sputtering.
If you are driving at a consistently high speed and your engine suddenly starts sputtering before returning to normal, this might mean that the fuel pump cannot provide a constant stream of fuel to the engine at the ideal pressure.
Stalling at high temperatures.
Stalling with a combination of a high internal temperature in your vehicle could mean there is a problem with your fuel pump’s motor.
Loss of power under load.
If you experience a loss of power when you are driving uphill, carrying a heavy load or even while accelerating, this may indicate the fuel pump is weakening because it cannot keep up with the higher demands of your vehicle.
Car surging.
Irregular resistance inside the fuel pump motor may cause vehicle surging and indicates a fuel pump in need of repair. Surging feels like the gas pedal has been used. However, it occurs at a random, consistent speed. If this happens often, it may be because of problems within the fuel pump.
Car will not start.
If the fuel pump fails completely, the vehicle will refuse to start. The engine will still crank when the key is turned, but it will be unable to start due to the lack of fuel. A no-start situation can also be caused by a variety of other issues, so having the vehicle accurately diagnosed is highly recommended.
Here are some signs of a faulty fuel injection system:
- Your “Check Engine/Service Engine Soon” light turns on.
- Rough idle or engine stalls.
- Your engine vibrates or misfires.
- You notice a fuel leak and/or a fuel odor.
- Your engine surges.
- Your vehicle’s fuel economy declines.
