INJECTOR CHECK


CHECK THE OPERATION SOUND
caution Beware that the operation sounds of other injectors can be heard even if the injector that is being inspected might not be operating.

1.Use a stethoscope to listen to the operation sound (clicking) of the injectors while the engine is idling or cranking.
2.Verify that the operation sound increases with the engine speed.
note If the operating sound cannot be heard, inspect the injector actuation circuit.

MEASUREMENT OF RESISTANCE BETWEEN TERMINALS
1.Disconnect the injector connector.
2.Measure the resistance between terminals.
Standard value: 10.5 - 13.5 Ω (at 20°C)
3.If the resistance is deviates from the standard value, replace the injector.
4.Connect the injector connector.

CHECK THE INJECTION CONDITION
1.Following the steps below, bleed out the residual pressure within the fuel pipe line to prevent flow of the fuel (Refer to ).
2.Remove the injector.

3.Assemble the following special tools as shown in Fig.

  • Injector test set (MD998706)
  • Injector test harness (MB991607)
  • Injector test adaptor (MD998741)
  • Injector test holder assembly (MB991976)
4.Connect the M.U.T.-III to the diagnosis connector.
5.Turn the ignition switch to ON position (But do not start the engine).
6.Select "Item No. 07" from the M.U.T.-III actuator test to drive the fuel pump.

7.Activate the injector and check the atomized spray condition of the fuel.
The condition can be considered satisfactory unless it is extremely poor.
8.Stop the actuation of the injector, and check for leakage from the injector nozzle.
Standard value: 1 drop or less per minute
9.Without the fuel pump operation, operate the injector to draw the fuel out.
10.If the spraying is extremely poor or the fuel leakage from the injector nozzle deviates from the standard value, replace the injector.
11.Disconnect the M.U.T.-III.