Deutz-Fahr 734 – ECU: Oil Pressure Too High - Warning Threshold Reached

The Engine Control Module (ECU) has detected an oil pressure reading that is above the normal operating range for a sustained period. High oil pressure can lead to damaged seals, gaskets, and oil filters, and may indicate a mechanical restriction that prevents oil from properly lubricating critical engine components.

• 1011 Series
• 1011F
• 2011 Series
• 2012 Series
• 2013 Series
• BF3L2011
• BFM1013
• F3M1011F
• F4M1011F
• F4M2011
• TCD 2.9 L4
• TCD 3.6 L4
• TCD 4.1 L4
• TCD 6.1 L6
• TCD 7.8 L6

1. 1

   Observe initial cold start pressure - high pressure is normal when cold due to higher oil viscosity, but should drop as the engine warms up.

2. 2

   Check engine oil level and condition - ensure it is not overfilled, the correct viscosity is used for the climate, and there is no contamination or excessive sludge.

3. 3

   Inspect the oil filter for severe clogs or incorrect fitment causing a restriction.

4. 4

   Verify actual oil pressure with a mechanical gauge connected to the sensor port to determine if the issue is a faulty sensor (electronic) or a true high-pressure condition (mechanical).

1. 1

   Disconnect and Remove (If Faulty Sensor Confirmed)

   Disconnect the electrical connector from the oil pressure sensor. Use the appropriate socket or wrench to remove the old sensor from the engine block.

2. 2

   Install New Sensor

   Ensure the threads on the new sensor and the engine block are clean. Install the new sensor and tighten it to the manufacturer's specified torque. Do not overtighten.

3. 3

   Reconnect and Verify

   Reconnect the electrical connector. Clear the fault codes using a diagnostic tool and run the engine to verify that the fault does not return.

4. 4

   Locate the Valve (If Stuck Relief Valve Suspected)

   The oil pressure relief valve is often located on the cylinder block, sometimes behind the oil cooler or under a hexagonal cap nut (e.g., on the front face of the cylinder block, above the starter motor).

5. 5

   Remove and Inspect

   Unscrew the cap and withdraw the spring and valve plunger.

6. 6

   Inspect Components

   Check the valve plunger for scoring, pitting, or signs of sticking in its bore. Inspect the spring for weakness or breakage; verify free length if specs are available (e.g., 2.86 inches / 72.64 mm for certain models).

7. 7

   Clean or Replace

   If the valve is only lightly pitted, it may be possible to lap it back into its seat using a fine metal polish. However, for a confirmed fault, replacement of the valve and spring is the recommended and most reliable repair.

8. 8

   Reassemble

   Install the new or cleaned valve components in the reverse order of removal.

9. 9

   Verify Repair

   Start the engine, allow it to warm up, and monitor the oil pressure to ensure it is within the normal range.