Why does the car fail to start when the fuel pump is not supplying oil?
3 Answers
There are several reasons why a car fails to start when the fuel pump is not supplying oil: Low fuel level: If the car has very little fuel or the fuel gauge shows it is below the red line, it naturally won't start. When you find that the car won't start, the first thing you should do is check the fuel gauge to see if there is any fuel left. Additionally, never wait until the fuel tank is empty before refueling. This not only affects the lifespan of the engine but also the fuel pump. Operating the fuel pump without fuel can even be dangerous. Crankshaft position sensor failure: The crankshaft position sensor is one of the most important sensors in an electronically controlled fuel injection engine, especially in centralized control systems. It is also a shared sensor for both the ignition system and the fuel injection system. The function of the crankshaft position sensor is to monitor the position of the crankshaft, allowing the engine's computer to detect the speed signal. If the crankshaft position sensor fails, the computer cannot detect the speed signal and thus cannot determine whether to ignite, resulting in the car failing to start.
The car won't start, and the fuel pump isn't delivering fuel. I've encountered this issue several times while repairing my own car. The most common cause is a faulty fuel pump motor, which could be due to aging, wear, or power supply issues. First, check the fuse—look for the "fuel pump" label in the fuse box to see if it's blown. If replacing it doesn’t work, inspect the relay, which controls the current flow; if it’s faulty, it won’t supply fuel. Poor electrical connections are also common, such as loose or corroded wiring, leading to unstable voltage. Additionally, a clogged fuel filter can obstruct fuel flow, causing insufficient pressure, so try replacing the filter regularly. Maintaining the fuel system is crucial—neglecting it can lead to breakdowns at critical moments, like during long drives. Pay attention to the fuel pump's sound when starting the car; if there’s no humming noise, it’s likely malfunctioning. Get it checked at a professional shop promptly to avoid further issues.
Failing to start and the fuel pump not delivering oil are common issues. I often remind friends to pay attention to several key points. The main cause is usually a faulty fuel pump, such as a burnt internal motor or a clogged pump body, which prevents oil from reaching the engine. Next, check the vehicle's electrical system—low or unstable battery voltage can affect the fuel pump's operation. Use a multimeter to measure if the voltage is around 12 volts. Relays and fuses are also prone to issues; they are located in the fuse box, so check them one by one. Fuel line leaks or air intake can cause a drop in system pressure, leading to fuel delivery failure. Don’t overlook the vehicle's computer control module, as signal errors can result in incorrect commands. For regular maintenance, it’s recommended to replace the fuel filter every 20,000 kilometers to prevent clogs. If you encounter this problem, avoid forcing the engine to start, as it can cause damage. Pull over immediately and call for a tow truck. Safety first—a mechanic can quickly diagnose the issue using a diagnostic tool connected to the computer.
