How Does A Motor Fuel Pump Work?
Many cheap old-school vacuum testers can read the mechanical pressure of the fuel pump and the vacuum pressure. As the diaphragm is pushed up, the gasoline above it is pressurized and moves out of the pump and into the fuel line to the carburetor. The fuel pressure is usually designed to be 2-6 psi, depending on the manufacturer. The vacuum created by the movement of the membrane draws fuel to the chamber, aided by the siphon already present in the fuel system. Most modern vehicles use the gerotor design, which is best for high-pressure, high-volume electrical applications. A gerotor pump works by turning a gear that operates an inner ring wheel with teeth in the ring.
When an accident is recorded, the PCM has the ability to cut off the power to the fuel pump by turning off the fuel pump relay. A fuel pump is an essential part of a car that is powered by a combustion engine. Older motorcycle engines don’t need brandstofpomp fuel pumps at all because they have gravity fuel from the fuel tank or under high pressure to the fuel injection system. Direct injection diesel and gasoline engines use a mechanical pump to generate the highest pressures needed for operation.
The ignition switch does not provide the current needed for the pump to run; it provides a smaller current that activates a relay designed for the pump’s operating current. It is common for the fuel pump relay to rust and stop working; this is much more common for the fuel pump itself to fail. Modern engines use a solid-state control that allows the fuel pressure to be controlled by modulating the pulse width of the pump voltage. This extends the life of the pump, provides a smaller, lighter pump and reduces the power consumption of the pump. Replacing a mechanical fuel pump with an electric pump removes an accessory load from the engine and reduces the fuel consumption of the engine. In addition, the fuel supply can be monitored more accurately by the electronic control unit.
It is similar to that of a piston pump, but the high-pressure seal is stationary, while the smooth cylindrical piston glides through the seal. These pumps usually operate at a higher pressure than diaphragm type pumps. Specific designs vary, but in the most common configuration, these pumps are mounted on the side of the injection pump and driven by the camshaft, either directly or via a push rod.
These pumps are no longer in use because cars have switched from carburetors to fuel injection systems. Sometimes the fuel pump generates full pressure when the starter starts, but it stops working after starting and the engine stops quickly. This indicates a problem with a motor sensor or powertrain control module. It’s not a fuel pump failure, but it’s often misdiagnosed as a faulty fuel pump. Under normal circumstances, it is not uncommon for a pump to last the entire life of the vehicle. When it finally stops, it’s because the engine is worn out and can’t develop enough torque to generate the right fuel pressure.