Replacing Fuel Pressure Regulator

Replacing fuel pressure regulator (M42, M43, M43TU, M44)


Turn off ignition.







After function check of Digital Motor Electronics (DME),
Testing and Inspection
or after checking fuel pump supply pressure,
Component Tests and General Diagnostics
disconnect vacuum hose (1) and if necessary hose (2).







Disconnect vacuum hose.
Mark installation position of connection for vacuum supply line on injection pipe.







Version 1:
If pressure regulator is secured with a nut:
Release screws and remove bracket.







Release nut (3) and remove clamping bracket.







Turn fuel pressure regulator and remove.

Installation:
Replace sealing rings (1) and (2). When replacing, observe nominal pressure stamped on fuel pressure regulator; only regulators with the same nominal pressure may be fitted.

Further information on troubleshooting in:
Checking fuel delivery pressure, refer to Checking Delivery Pressure of Fuel Pump.
Component Tests and General Diagnostics







Installation:
Pressure regulator must be pushed firmly home to enable the clamping bracket to be fitted.







Version 2:
Version with a retaining bracket:
Remove retaining bracket (2).







Installation:
To prevent damage to the vacuum hose, ensure that recess (3) is aligned with vacuum connection (4).







Turn fuel pressure regulator and remove.

Installation:
Replace sealing rings (1) and (2). When replacing, observe nominal pressure stamped on fuel pressure regulator; only regulators with the same nominal pressure may be fitted.

Further information on troubleshooting in:
Check fuel delivery pressure, refer to : Checking Delivery Pressure of Fuel Pump.
Component Tests and General Diagnostics






Version 3:
If secured by a circlip;
Pull off vacuum hose (1).







Remove circlip (1).







Turn fuel pressure regulator and remove.

Installation:
Replace sealing rings (1) and (2). When replacing, observe nominal pressure stamped on fuel pressure regulator; only regulators with the same nominal pressure may be fitted.

Further information on troubleshooting in;
Check fuel delivery pressure, refer to : Checking Delivery Pressure of Fuel Pump.
Component Tests and General Diagnostics