Massey Ferguson E157.17 – Engine Control Unit (ECU) / EEM (Electronic Engine Management): Rail pressure controller, Negative deviation / Fuel Rail Pressure Not Developed

The engine is unable to develop sufficient fuel rail pressure during startup. Specifically, the controller does not detect the minimum required 10 MPa (1450 psi) of fuel rail pressure after cranking the engine for approximately 5 seconds.

• 7616
• 5612
• 7622
• Interim Tier 4 (2012-2015)
• 7614
• 5611
• 7615
• 5610
• 5613
• 7620
• 5609
• 7618
• 5608
• 7619
• 7626
• 7624
• 4707
• 4708
• 4709
• 4710

1. 1

   Verify that there is fuel in the tank and that the fuel system is properly primed (air in the fuel lines is a primary cause).

2. 2

   Inspect the primary and secondary fuel filters for severe blockages, water, or gelling that could restrict low-pressure fuel supply.

3. 3

   Check the Fuel Rail Pressure Relief Valve (PRV) for leakage (stuck open or opening prematurely).

4. 4

   Inspect high-pressure injector lines and the high-pressure pump for external leaks or excessive internal return flow.

1. 1

   Prime the System

   Manually prime the fuel system to purge any air pockets. Attempt to crank the engine.

2. 2

   Service Fuel Filters

   If priming does not resolve the issue, replace the fuel filters and re-prime the system.

3. 3

   Test/Replace the PRV

   Perform a return flow test on the fuel rail pressure relief valve. If fuel is bypassing the valve during cranking (before maximum pressure is reached), the valve is faulty. Remove the old valve in a highly clean environment (to prevent microscopic contamination) and install a new OEM relief valve.

4. 4

   Inspect Pump/Injectors

   If the PRV is intact, the high-pressure fuel pump or the fuel injectors may have excessive internal leakage (bypassing fuel back to the tank). Perform an injector leak-off test to isolate the faulty component and replace it.

5. 5

   Clear Codes

   Use an AGCO diagnostic tool (such as WinEEM3s or WinEEM4) to clear the E157.17 fault code and verify the repair by monitoring live rail pressure data during startup.