Diagnosing fuel pressure problems is often tricky because the problem can be more than just the fuel pump. Responsible for delivering pressure to the fuel injectors, this pump is electrically brandstofpomp controlled by the car’s computer using a fuel pump relay. A fuel pressure regulator is used to control the pressure that may be in the fuel pump or externally on the fuel rail.
The fuel pump should only run when the engine is running and sending fuel from the fuel tank to the engine. If the fuel pump is running continuously when the engine and ignition switch are turned off, the list below may be to blame. The causes of no fuel pressure, but the operation of the pump can be numerous. When the relay is faulty, it can cause the fuel pump not to receive power, causing it to not work. However, in classic cars with mechanical fuel pumps, the pressure is much lower, between four and six PSI. If you suspect that your fuel pump is not producing enough pressure, there are two tests you can perform.
Gate and screw pumps are cam-driven pumps that operate at half the engine speed for four-stroke engines and at the same speed in the case of two-strokes. The pump is similar to that of a radial piston pump, but instead of a piston, it has a machined plunger that has no seals. When the piston is in the upper dead center, the injection into the cylinder is terminated and returned to its downward stroke by a compression spring. The fuel is then pressed through a stop check valve to prevent flow back to the injector nozzle at a pressure of more than 18,000 psi.
This allows you to somehow start your car with a faulty fuel pump and give an idea about the actual failure of the car’s engine. Diaphragm pumps use a composite diaphragm, which bends up and down over a fuel container. The vessel has an inlet and an outlet, each with a non-return valve to ensure a one-way movement of the liquid.
If the voltage drop is high, look for a corroded or overheated connector, a faulty relay, or even a worn cable. Some replacement fuel pumps come with a heavy-duty connector that is used to replace the car’s original connector. As mentioned above, high resistance in an electrical circuit reduces the amount of voltage downstream from the high resistance point. Therefore, before judging a fuel pump, it is important to make sure that the full battery voltage is available on the fuel pump connector while the pump is running. The retention pressure is checked at the same time as the pressure of the fuel system. After the engine is turned off and the fuel pump stops working, the pressure of the fuel system will decrease slightly and then it will remain stable for at least five minutes.
A non-return valve is located in the inlet and outlet ports of the pump chamber to allow fuel to flow in only one direction. In addition, the volume in the pump chamber increased, which reduced the pressure. The return movement from the diaphragm to the upper dead center is achieved by a diaphragm spring, where the fuel in the pump chamber is compressed through the output port and into the carburetor. Therefore, the pressure at which the fuel is expelled from the pump is limited by the force exerted by the diaphragm spring. Electric fuel pumps are usually located in the fuel tank, to use the fuel in the tank to cool the pump and ensure a constant supply of fuel. In the past, mechanical fuel pumps were much more common, sometimes connected outside the fuel tank.
When your vehicle starts, the fuel pump relay should also power your car’s fuel pump. If you drive too far without the engine being checked, it will overheat and need to be replaced. Mechanical fuel pumps move fuel from the fuel tank to the engine under low pressure through the carburetor. The fuel is mixed with the air in the carburetor, the liquid is pumped into the engine. The camshaft turns a switch on the fuel pump that uses a diaphragm in the carburetor.
Prior to the widespread application of electronic fuel injection, most carburetor engines used mechanical fuel pumps to transfer fuel from the fuel tank to the carburetor fuel vessels. The two most commonly used fuel supply pumps are the mechanical diaphragm and plunger pumps. Diaphragm pumps contain a pump chamber whose volume increases or decreases by bending a flexible diaphragm, similar to the operation of a piston pump.