| Removing and installing fuel pressure sender |
| The fuel pressure sender -G247- (rail pressure sensor) is located in the high-pressure accumulator and continuously measures the current fuel pressure in the high-pressure system. It transmits a corresponding voltage signal to the diesel direct injection system control unit -J248-. |
| In the event of sender failure, pressure regulation is controlled using a map from the engine control unit. In back-up function, the maximum engine speed is limited to approx. 3000 rpm. |
Caution | Follow the rules for all work on the fuel system → Chapter. |
| Follow these instructions before starting work and while working on the fuel system. |
|
| –
| Clean threaded area around sender (e.g. with standard cleaning solution) before removing. Under no circumstances may dirt enter the hole of the high pressure accumulator. |
Note | Clean carefully; cleaning solvent must not enter the electrical connector. |
| –
| Dry off fuel pressure sender -G247-. |
| –
| Disconnect electrical connector at fuel pressure sender -G247-. |
| –
| Unscrew and remove fuel pressure sender -G247-. |
| –
| Extract dirt from high-pressure accumulator bore (threads and sealing surface). Do not use tools or other instruments for this purpose. |
Note | Seal off high-pressure accumulator bore immediately with a suitable plug to prevent dirt from entering. |
Note | t
| Check that sealing surfaces (deformable sealing lip) and threads on fuel pressure sender -G247- are undamaged. |
| t
| Also check sealing surface at high-pressure accumulator bore. |
| t
| The thread of the fuel pressure sender -G247- is coated with a lubricating lacquer. The thread must therefore be free of oil and grease. |
| –
| Screw in fuel pressure sender -G247- by hand. |
| –
| Tighten sender. Specified torque → Item |
| –
| After installation, run engine at moderate speed for several minutes and then switch off. |
| –
| Check fuel system for leaks. |
| –
| Then test drive the vehicle with at least one full acceleration. Check high pressure part of fuel system again for leaks. |
|
|
|
