How can bad Fuel Pump affect emissions? Modern engines depend on accurate fuel delivery, usually maintaining fuel pressures of 35 to 65 PSI (Pounds per Square Inch) for optimal combustion. The pump is not supplied with the right quantity of fluid, so it creates an unbalanced ratio of air and fuel, which negatively influences the purity of the emission.
When insufficient fuel is delivered, it can cause incomplete combustion, which increases the amount of harmful pollutants like CO and HC. A study published in 2022 of emissions from vehicles with fuel pump issues found they had CO emissions at 40% higher than they should be in normal conditions. This happens because when an engine runs lean (too much air, not enough fuel), it has trouble burning the fuel all the way.
A rich fuel mixture due to a faulty pump regulator can also lead to excessive emissions. In this situation, unburned fuel escapes to the atmosphere through the exhaust system, resulting in increased HC emissions and reduced efficiency of the catalytic converter. Catalytic converters are built to reduce the most toxic gases in a vehicle’s exhaust, but the more unburned fuel that has to pass through, the shorter a converter’s life, which generally is 80,000 to 120,000 miles. A faulty converter can cost $1,500 or more to replace, so maintaining the fuel pump is key.
Fuel system diagnostics, including fuel pressure gauges and onboard diagnostics OBD-II scanners pinpoint where emissions are spiked. One case study from 2021 described a sedan that failed an emissions test due to increased levels of HC. Diagnostics showed a bum pump that could only deliver half the pressure needed. After changing the pump, the car passed the test with 30% fewer emissions.
As Henry Ford said, Quality is doing it right when no one is looking. This approach also highlights the significance of correcting problems such as a faulty fuel pump before they become larger complications. Replacing a fuel pump usually runs $200 to $1,000, depending on the vehicle, yet can save thousands in emissions-related repairs and fines.
We recommend going to Fuel Pump for professional service and quality fuel pump products.