Case IH 3313 – Engine Control Unit (ENG / EDC): Cylinder 6 BIP Search Failure - Too Many Unsuccessful Searches - Rail Pressure Drop Rate too High

The engine control system monitors the slight drop in fuel rail pressure to determine the exact millisecond the fuel injector opens. This code is triggered when the system cannot detect the BIP for Cylinder 6 after multiple attempts because the pressure drop rate in the common rail is excessively high. This typically indicates a massive fuel pressure loss during Cylinder 6's injection window, which is usually caused by a mechanically failed injector (bypassing too much fuel to the return), a stuck open injector, or a severe leak in the high-pressure line feeding that cylinder.

• Case IH Magnum 235 – 340 (Series 4)
• Case IH Steiger series (350 to 600 HP)
• Various other Case IH / New Holland tractors sharing the same engine management architecture

1. 1

   Inspect the high-pressure fuel line feeding Cylinder 6 and the injector body itself for any obvious external fuel leaks.

2. 2

   Perform an injector leak-off (return flow) test to measure return flow; if Cylinder 6 shows significantly higher return volume than the others, the injector has failed internally.

3. 3

   Use a diagnostic scan tool to monitor the fuel rail pressure sensor readings while cranking and running to ensure the sensor is accurately reporting pressure and not skewing the data.

4. 4

   Check the wiring harness and connector at the Cylinder 6 injector for chafing, corrosion, or loose pins, which could cause erratic injector operation.

1. 1

   Depressurize the System

   Turn off the engine and allow sufficient time for the high-pressure fuel rail to depressurize before opening the system.

2. 2

   Remove Components

   Disconnect the electrical connector from the Cylinder 6 fuel injector. Remove the high-pressure fuel line connecting the fuel rail to the Cylinder 6 injector.

3. 3

   Extract the Injector

   Remove the injector hold-down clamp/bolt and carefully extract the Cylinder 6 fuel injector from the cylinder head.

4. 4

   Clean the Bore

   Thoroughly clean the injector bore and ensure the old copper sealing washer is removed from the bottom of the hole.

5. 5

   Install New Parts

   Install the new or remanufactured fuel injector using a new copper sealing washer and new O-rings.

6. 6

   Replace the Fuel Line

   Install a new high-pressure fuel line for Cylinder 6 (high-pressure lines are generally single-use and should not be reused once torqued). Torque all fittings to the OEM specification.

7. 7

   Bleed and Clear

   Prime/bleed the fuel system to remove air. Use a diagnostic tool to clear the 3313 fault code.

8. 8

   Test Run

   Start the engine, check for leaks, and verify that the code does not return and the engine runs smoothly.