Identifying a failing fuel pump involves recognizing several cardinal symptoms affecting both engine performance and fuel delivery. One of the earliest signs is a difficulty in starting the vehicle because a deteriorating Fuel Pump may not be able to provide the required pressure of usually 40-60 psi in a fuel-injected engine. This usually indicates that the pump isn’t able to sustain adequate fuel pressure to the injectors when the crank time is longer than normal, or it takes several cranks before the engine finally starts.
Other common symptoms of an old and failing fuel pump include a loss of power upon acceleration, especially under high-demand conditions such as towing and uphill driving. As fuel pumps start to wear out, they are unable to support fuel demand, thus resulting in sputtering or even a stalled engine. A weak pump causes the fuel flow to be inconstant, thus upsetting the air-fuel mixture and leading to lower power delivery. Acceleration will be delayed and fuel economy will also visibly deteriorate-in many cases, a drop of 10-15%-since the engine would consume more due to a lack of sufficient fuel.
Noises from the fuel tank area are usually loud indications of problems in the pump. Most of the fuel pumps work quietly, and due to this fact, any very loud whining or buzzing noise points to internal wear or a clogged filter. This may even get louder with the decrease in fuel level since the pump would be forced to struggle more in the absence of fuel around it as a coolant. Keeping it at least a quarter full will help maintain proper cooling. Frequent replacement of fuel filters every 30,000 miles will also prevent contaminants from reaching the pump and extend life and performance.
Other possible influences a malfunctioning fuel pump can have include engine misfires or unexpected stalls. This is where inconsistent fuel delivery cannot provide the constant supply the engine requires. When not enough fuel reaches the engine, there can be a resultant misfire or rough idling, even resulting in a complete stall. Most times, these signs worsen over time, so it is of great essence that such issues should be addressed on time to avoid further complications.
It can also turn on in the case of low fuel pressure due to a failing fuel pump. The ECM monitors the performance of the fuel system. In most cases, an out-of-spec fuel pressure will make the computer set a diagnostic trouble code. Some common codes include low fuel rail pressure, such as P0087, which may indicate problems with the fuel pump. You can confirm this with an OBD-II scanner reading. It may give you some information to tell if you need a replacement.
As Carroll Shelby, the automotive icon once said, “Performance and reliability do not happen by accident.” Thus, just like early symptoms are watched out for, timely changes of fuel filters become very important in order to avoid sudden failures of the pump. A quality replacement Fuel Pump buys appropriate, reliable operation, efficient fuel delivery, and optimal engine performance. Taking heed of these symptoms well in advance and being able to handle them saves fuel, enhances road safety, and keeps your running mate going for several miles yet to come.