1990-93 VW Passat
The differential pressure regulator is mounted to the mechanical air mass sensor (see exploded view illustration of the fuel distributor. The pressure regulator is operated by the Motronic control unit. The regulator controls the pressure differences between the upper and lower chambers in the fuel distributor. There is no service procedure that requires disassembly of the airflow sensor.
- Relieve the fuel system pressure. See "Relieving Fuel System Pressure."
- Disconnect the wiring.
- Clean any dirt away from the fuel line fitting and remove the fitting.
- Remove the 2 screws to remove the regulator. The screws are made of non-magnetic material. If the screws must be replaced, make sure they are non-magnetic.
- Installation is the reverse of the removal procedure.