Using Stethoscope And Voltmeter

Checking operating sound using a stethoscope.
1. Check the injector for clicking at idling. Check the sound for getting shorter in intervals as the engine speed increases.
  
  Fig 1: Checking The Injector For Clicking With Stethoscope
  Courtesy of KIA MOTORS AMERICA, INC.
  
  CAUTION: Be sure that the sound from an injector is not transmitted along the delivery pipe to an adjacent injector(s) not in operation.
2. If a stethoscope is not available, sense the injectors? operation with your finger. If no vibration is felt, check the wiring connector, injector or injection signal from the ECM.
Fig 2: Checking The Injector For Clicking With Fingers
Courtesy of KIA MOTORS AMERICA, INC.
Measuring the resistance between the terminals.
1. Disconnect the connector at the injector.
2. Measure the resistance between the terminals.
  
  Fig 3: Measuring Injector Resistance
  Courtesy of KIA MOTORS AMERICA, INC.
3. Connect the connector to injector.