The fuel pump is a crucial component of a vehicle's fuel supply system. Its core function is to provide a stable and sufficient supply of fuel to the engine. Specifically, it is located inside the fuel tank. A motor drives the pump body to rotate, creating negative pressure that draws fuel from the tank and delivers it to the engine's fuel supply lines. This process ensures that the engine always receives the required fuel, maintaining normal power output.
Diaphragm fuel pumps are characterized by their simple structure. However, due to the effects of engine heat, particular attention must be paid to ensuring pumping performance at high temperatures and the durability of the rubber diaphragm against heat and fuel. The maximum fuel delivery capacity of a typical fuel pump is 2.5 to 3.5 times greater than the maximum fuel consumption of a gasoline engine. When the pumping capacity exceeds fuel consumption and the carburetor float chamber needle valve is closed, the pressure in the fuel pump outlet line increases, which in turn affects the pump, shortening the diaphragm stroke or causing it to stop.
Electric fuel pumps are not driven by a camshaft, but rather by electromagnetic force, which repeatedly draws the pump diaphragm. This type of electric pump allows for flexible installation and prevents air lock. The main installation types of electric fuel pumps for gasoline injection engines are installed in the fuel supply line or in the fuel tank. The former has a larger layout range and does not require a specially designed fuel tank, making it easy to install and disassemble. However, the fuel pump has a long suction section, which is prone to air blockage and has a high working noise. In addition, the fuel pump must not leak. This type is rarely used on new vehicles. The latter has a simple fuel line, low noise, and low requirements for fuel leakage. It is the current main trend.
ATH® is one of the manufacturers of Electric Fuel Pump 906 089B in China
Electric Fuel Pump 906 089B
| Parameter | Description |
|---|---|
| Applications |
VW TOUAREG (2002-2020 3.0L) AUDI Q7 (2006-2015, 2003-2008) |
| Ref No. |
#10639 701557507092 7.50112.50 IKO 906 089B |
| Technical Parameters |
Pressure: kPa Flow: L/H |
When the fuel pump does not work, first check the fuel pump circuit and then check the fuel line pressure.
(1) Circuit check
Measure the fuel pump power supply terminal. The power supply terminal voltage should be the battery voltage. If the voltage is abnormal, consider that the fuel pump relay or fuel pump related wiring harness is faulty.
(2) Oil pressure check
The fuel pressure is measured by the fuel pressure gauge. The pressure should be around 0.4MPa (depending on the engine model, the specific pressure value will also vary). If the pressure is abnormal, it may be that the fuel pressure regulator, fuel pump or filter has a fault.
