Intallation examples of electric fuel pumps illustrated in block diagrams
Information on diagnostics
What is the difference between in-line pumps and in-tank pumps? When are pre-feeder pumps needed? What are the different installation options for electric fuel pumps? This article tells you all you need to know.
- In-line pumps are inserted in the fuel line.
- In-tank pumps are installed in the fuel tank. In the case of in-tank pumps, other components, such as fluid-level sensors or diagnostic systems, can be installed directly in or on the pump module.
Mixed and special systems, such as semiin- tank pumps (e. g. in the Golf II), are not described here.
One or two fuel pumps are connected in series, depending on requirements.
- A single fuel pump
- Two fuel pumps (pre-feeder pump, main pump) Pre-feeder pumps deliver the fuel to the main pump under low pressure
- A single two-stage fuel pump
These installation options are illustrated in the adjacent diagrams
In-line fuel pump
In-tank fuel pump
in- line pre-feeder pump with in-line main pump
In-tank- pre-feeder pump with in-line main pump
in-line two-stage fuel pump
in-tank two-stage fuel pump, fuel pump in reservoir ("swirl pot"); stages sealed against one another
