Suction Jet Pump, Removing And Installing
The fuel tank is divided into a left and a right chamber. To move the volume of fuel from the left fuel tank chamber to the right to the baffle housing -1- of the fuel delivery unit -2-, a suction jet pump -3- is utilized.
Suction Jet Pump Function
The function of the suction jet pump is based on a simple physical principle: a suction jet from the electrical fuel pump is compressed by a nozzle in the suction jet pump and is thereby accelerated. This acceleration causes the surrounding fuel to be drawn in and be forced to the baffle housing of the fuel delivery unit.
Malfunctions due to Faulty Suction Jet Pump
Vehicle breakdown due to faulty suction jet pump.
- If the suction jet pump is faulty, the vehicle with a fuel tank up to 1 /4 filled may stop running due to a lack of fuel.
If the suction jet pump does not function, up to 15 liters of fuel (up to approximately 1 /4 of the fuel tank volume) remains in the left section of the fuel tank that cannot be extracted by the fuel delivery unit.
If the vehicle stops running due to lack of fuel, though the fuel tank is up to 1 /4 filled, proceed as follows:
-- Connect the Vehicle Diagnostic Tester
-- Switch the ignition on.
-- Select and start OBD mode.
- Drivetrain
- Engine
- 01 - OBD-capable systems
- 01 - Engine electronics
- Basic setting
- Drain fuel tank
-- Start the basic setting without measured values: the fuel pump starts.
If the fuel pump is OK, but no fuel is being delivered:
-- Fill with approximately five liters of fuel.
-- Start the engine.
If the engine now starts:
-- The suction jet pump is not available separately; replace the fuel tank. Refer to FUEL TANK, REMOVING AND INSTALLING .