The failure of the fuel pump pressure relief should replace the following things:
1. For general pressure relief, either there is a problem with the check valve, or the performance of the pump core is insufficient. Just replace a check valve;
2. Before purchasing a pump core, you must first know that the same pump core has multiple varieties with different performances. Be sure to ask clearly when purchasing or replacing, in order to prevent mismatch and pressure relief;
3. The car electronic oil pump has a small ball in the oil outlet. It acts as a one-way valve and if it goes out of round or gets stuck a bit, the gas will go back to the tank.

Fuel pump failures are caused by:
1. Quality problems of oil products;
2. The fuel pump is not equipped with a filter;
3. The oil level is too low for a long time;
4. The quality of the fuel pump itself;
5. Supplementary question: If it is not a gas engine, the fuel oil level light must be added immediately, and it is best to add it when the oil level meter is low. If it is a gas engine, you should do the following 2 points: maintain the oil level of 13 in the fuel tank. Change gasoline regularly.