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Home >> BMW >> 2003 >> M5 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System & Component Testing >> Fuel System >> Fuel Control >> Preliminary Check
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Preliminary Check

  1. Injectors should be tested using DISplus/GT1 for resistance, power supply, status display-fuel injection signal, and ECM final stage transistor activation. These test functions are found under the oscilloscope preset list. Install universal adapter, diagnostic cable, negative lead to ECM ground and positive lead to the ground activation circuit for the injector. This test is performed with the engine cranking or running.
  2. Fuel supply hardware should be visually inspected for damage that can affect pick-up, transfer, pressure and return. The fuel tank must be drained first before removing the service access cap to perform any repair. The fuel filter, fuel pressure regulator, electric fuel pump, right fuel level sensor and siphon jet are accessed through the service access cap. Remove the single 6-pin electrical connector (2 pins for the fuel pump, 2 for each level sensor-left/right). Remove the fuel supply line by releasing the quick release coupling. Fuel tank is secured by 2 straps to the body.