Recognizing signs that show your fuel pump needs servicing is integral to maintaining your car running condition and avoiding unwanted breakdowns. A very important indication has to do with low pressure of fuel, which is normally measured using a gauge that is usually attached to the fuel rail. Most vehicles do need a fuel pressure of around 30-80 psi, depending on each model. If the reading falls below that range, then it very well may be due to a weak fuel pump, in other words, low fuel pressure, which isn’t able to provide adequate fuel delivery required by the engine. Possible problems it may cause are poor acceleration, stalling, or hesitation.
Other unusual noises, including whining sounds coming from the fuel tank, also signify strain on the pump. The wear on the fuel pump is more evident on high-mileage vehicles-usually those over 100,000 miles-and whining noises are common signs that a pump is near the end of its life. For this reason, mechanics recommend servicing or replacing the pump at around this mileage as a form of preventive measure against sudden failure; a new fuel pump can last anywhere from 100,000 to 150,000 miles.
Frequent engine misfires and hard starts are symptoms of inconsistent fuel supply and may mean the pump is not operationally correct. Most engines normally require a very precise air-to-fuel ratio for easy operations; an erratic fuel pump breaks this critical balance, leading to an engine struggle or failure to start. Mechanics diagnose this through tests on the flow rate of the pump, usually quantified in LPH. For example, a healthy pump would yield around 90-130 LPH whereas a failing one would barely manage this quantity.
Other symptoms of the failing pump include a noticeable fuel economy decline: once it isn’t performing right, fuel economy drops 10-20%, and over time, that translates into higher costs for fuel. Keeping on top of its routine maintenance checks, such as fuel filter and fuel line inspections every 30,000-50,000 miles, will go a long way in extending its life and preventing costly repairs.
For a reliable Fuel Pump and further help in determining approximately when maintenance will be needed, refer to Fuel Pump.