Because a failing Fuel Pump plays such a key role in delivering the proper amount of fuel to maintain system pressure, it can cause check engine light codes to show for many systems. The fuel pump, is responsible for putting the proper amount of gas into the engine, at the accurate pressure, which is usually between 35 and 65 PSI depending on the engine. The check engine light on your dashboard lights up when the sensors detect the malfunctioning pump and send signals to the OBD-II system.
Diagnostic trouble code (DTC) ranging from P0087 (Fuel Rail/System Pressure Too Low) to P0230 (Fuel Pump Primary Circuit Malfunction) and P0250 (Injection Pump Fuel Metering Control) are some of the most common codes associated with a defective fuel pump. “P0135” – Low Pressure “098” O2 Sensor Circuit Issue “023” – Air Lock Fuel Metre.
For example, in a 2022 case study, we discussed a compact sedan that had generated a P0087 code but had a failing fuel pump that was operating at only 50 percent efficiency. The diagnosis was that the pump was producing only 20 PSI under load, a far cry from what the engine needed. It was replaced and it recovered the vehicle by 30% performance.
Check engine codes can also be generated from voltage inconsistencies. Fuel pumps need constant 12 to 14 volts to work properly. Corroded connectors, melted wires, or malfunctioning relays can break the power supply to the fuel pump, lowering its performance and bringing up error codes like P0230. Checking the voltage at the pump terminals with a multimeter can help pinpoint these types of issues.
Pump failure and error codes can also be caused by fuel contamination or a clogged fuel filter. Keeping your car well-maintained (that includes replacing fuel filters at 20,000- to 30,000-mile intervals) will avoid these problems and prolong a pump’s natural life, which is between 100,000 and 150,000 miles.
Henry Ford said, “Before everything else, getting ready is the secret of success,” and applying it to vehicle maintenance. If you address these early signs of a failing fuel pump, you will prevent costly repairs. Replaced a defective pump generally costs between $200 and $1,000, based on the car, but can provide reliable performance and prevent septic problems.
Visit Fuel Pump to read more about fuel pump diagnostics and maintenance.