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Injector Testing

Fuel Injectors can leak and bleed off fuel pressure causing hard or long starting and increased emissions. Injectors are leak tested using the Fuel Injector Leakage Tester.

Injectors should also be tested using the DISplus for:

Fig 1: "Good" Fuel Injector Scope Pattern
G04724680Courtesy of BMW OF NORTH AMERICA, INC.
NOTE:
  • Measurement is performed on the negative B- side of injector or trigger pin of EMS2000.
  • Vehicle voltage is present when injector is not active.
  • EMS2000 pulls voltage to ground causing injector to open.
  • When EMS2000 releases ground, injector closes and a voltage spike is produced because of the collapsed coil winding of injector.