When the Fuel Pump is at fault, the cold start failure rate increases significantly. According to the recall notice issued by the United States National Highway Traffic Safety Administration (NHTSA) in 2021, 23% of Toyota vehicles had more than 5 seconds delay in starting due to material defects of fuel pump impellers, encompassing 690,000 vehicles worldwide. Among them, 37% of the owners had already spent money on repairs for recurring ignition failure (an average of 3.5 times weekly) before the recall. Shop diagnostic equipment used by professionals has shown that the output pressure of the failed fuel pump can be 50% lower than the original factory specification. For instance, the normal fuel track pressure value for the Volkswagen EA888 engine is 400-600 kPa, while the faulty pump pressure will drastically drop to 180-250 kPa, inducing the air-fuel mixture deviation of more than ±8% (Bosch technical manual data).
Abnormal changes in fuel efficiency are another valuable indication. A test of 1,200 faulty cars carried out by the United States Environmental Protection Agency (EPA) in 2022 indicated that lowering fuel pump efficiency by 30% would increase fuel usage by 1.2 to 1.8 liters per 100 kilometers. In some cases, in the North American market in 2019, due to the fuel pump circuit board corrosion problem, Honda’s fuel consumption of the CR-V model rose from the actual tested 7.8L/100km certified by EPA to 9.5L/100km, suffering a class-action lawsuit and eventually paying a settlement of 32 million US dollars. Third-party laboratory tests show that when the rotational speed of the fuel pump motor is 15% lower than the design (usually 5000-7000 RPM), the flow rate of the fuel supply will decrease from 120L/h to 85L/h and cause a loss of engine power up to 18% (according to data in the SAE International paper).
Quantitative abnormal noise detection can accurately identify faults. Daimler Group’s technical bulletin in 2020 disclosed that the fuel pump bearing wear of the Mercedes-Benz M264 engine would generate high-frequency noise between 2000-4000Hz, with a sound pressure level exceeding 72dB (normal 55-60dB). The issue occurred at a frequency of 14% in vehicles with a mileage of over 80,000 kilometers. Evidence from the European Automobile Manufacturers’ Association (ACEA) maintenance database shows that 83% of complaints about abnormal fuel pump noise also have an oil pressure deviation of over ±25%. These vehicles have 3.2 times more likelihood of complete failure within three months.
Economic benefits of preventive maintenance are supported by concrete data. Bosch Automotive After-sales’ “White Paper on Fuel System Maintenance and Repair” in 2023 shows that replacing the fuel filter every 40,000 kilometers (costing around 40-80) can reduce the failure rate of the fuel pump by 61% and prevent the motor load increase caused by pump body blockage (current value more than 12A, normally 8-10A). Comparative figures show that the total cost of fuel pump replacement at 120,000 kilometers for vehicles that forego this maintenance (900-2,200) is 4.7 times the expense of the regular maintenance group. Volvo’s long-term follow-up study has confirmed that the use of fuel additives conforming to the ISO 16332 standard can extend the lifespan of fuel pumps from an average of 130,000 kilometers to 170,000 kilometers and reduce the wear rate of metal parts by 42%.
Fault code analysis by authoritative institutions provides decision-making basis. Based on CarMD’s 2.3 million North American market diagnostic data, when the P0087 fault code (fuel system low pressure) appears more than three times, the likelihood of fuel pump failure is 78%, and it is usually accompanied by abnormal fuel flow sensor data (the actual value is more than ±22% deviating from the ECU’s preset value). Tests conducted by the German TUV certified laboratory show that when the FPCM voltage is below 11V for 10 seconds, the protection mechanism can be triggered to shut off the fuel supply. The occurrence frequency of the phenomenon at high-temperature conditions (engine compartment temperature >85℃) is 2.3 times that at normal temperature conditions.