Electric gasoline pump is driven by electromagnetic force instead of camshaft. This kind of electric pump can freely choose the installation position and prevent the air resistance phenomenon.
The main installation types of electric gasoline pumps for gasoline injection engines are in the fuel supply pipeline or in the gasoline tank. The former has a large layout range, does not need to specially design the gasoline tank, and is easy to install and disassemble. But the oil pump suction section is long, easy to produce air resistance, work noise is also large, in addition to the requirement that the oil pump absolutely must not leak, the current new type of vehicle has been less used. The latter has simple fuel pipeline, low noise and low requirement of multi-fuel leakage, which is the main trend at present.
In operation, the flow rate of gasoline pump should not only provide the consumption of engine operation, but also ensure sufficient return flow to ensure the pressure stability and sufficient cooling of the fuel system. 
Website source: www.evpvacuum.com
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