a) With the engine running or when turning it over with the starter, use a phonendoscope to check by ear (by the sound of injected fuel) in the performance of the injectors, making sure that the injection frequency is proportional to the engine crankshaft speed.
b) If you don't have a phonendoscope, you can check the functionality of the injectors by touching them with your finger or a screwdriver.
If there is no sound or if it is unusual in nature, check the wiring, connector, injector, additional resistance of the injector, or the presence of a control signal from the electronic control unit.
2. Check the injector resistance. Disconnect the injector connector and use an ohmmeter to measure the injector resistance.
- Nominal resistance at 20°C - 13.4-14.2 Ohm
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If the resistance value or the control signal is outside the specified limits, replace the injector. Connect the injector connector.