Yes, a faulty fuel pump can have an impact on car emissions by preventing the right ratio of air to fuel necessary for efficient burning. Vehicles tend to need an exact mixture of fuel and air, so they will have fewer pollutants. If the fuel pump cannot supply the appropriate pressure-usually between 30-80 psi for most car models-the engine either runs too lean or too rich, both of which can result in increased emissions. More precisely, running rich implies elevated levels of carbon monoxide and unburned hydrocarbons, both serious pollutants regulated by emissions standards around the world.
This translates to older fuel pumps, especially those with mileage of over 100,000 miles, suffering efficiency losses of approximately 10-20%, resulting in erratic fuel delivery. This unpredictability causes the engine to work harder to produce constant power, which tends to lead to increased NOx emissions, among the most harmful to air quality. Industry professionals explain that fuel systems are among the most important areas to be properly maintained in order to meet regulatory emissions standards since even the tiniest inefficiency can lead to an unfavorable outcome from an emissions test and expensive corrective action.
Poor performance of the fuel pump also contributes 10-15% to poor fuel economy; such would culminate in increased fuel consumption and higher emissions over time. Drivers can feel this with increased frequency of visits to the gas station, showing something has been lost in fuel efficiency due to the improper delivery of the fuel. Mechanics usually recommend servicing or replacement of the Fuel Pump if the fuel efficiency falls below a certain threshold, as this will not only cut emissions but also offer long-term fuel cost savings.
The EPA has listed vehicles with faulty fuel systems, such as a malfunctioning pump, among the top causes of urban air pollution. Regular inspection and timely replacement of the fuel pump and other components involved go a long way in helping the vehicle meet such emission standards and thus run cleaner and more efficiently. Refer to Fuel Pump for quality fuel pump replacements.