If fuel delivery is erratic or poor, or if the fuel pump makes abnormally loud noises, test the pump power consumption using a BMW factory scan tool or equivalent to measure fuel pump power consumption through the EKP module, following the on-screen instructions to monitor fuel pump current. An alternate method involves installing a digital ammeter in the fuel pump circuit by first removing the rear seat to access the fuel pump and fuel level sender, then sliding the locking connector in the direction of the arrow to remove the electrical connector from the fuel pump. Use a voltmeter to verify that the battery voltage at the fuel pump connector is 12.6 volts with the fuel pump circuit actuated, charging the battery if necessary. Attach the digital ammeter between the pump lead and harness, connecting a jumper wire between the pump and harness while ensuring that the test leads do not short to ground. Activate the fuel pump and compare the ammeter reading with the specified values. Higher than normal power consumption may indicate a worn pump, leading to intermittent fuel starvation due to pump overheating and seizure, necessitating pump replacement. Conversely, lower than normal power consumption may suggest a blockage in a fuel line, so it is essential to check that the return line and pump pickup inside the
Fuel Tank are not obstructed before replacing the fuel pump.