Vehicles with a 1.4-/1.6-/2.0-liter petrol engine (except for 1.4 liter E7J engines).
Leaky fuel injectors make it difficult to start a hot engine, cause the engine to run erratically, and cause misfiring.
1. Start the engine and let it idle.
2. Use a stethoscope and, without turning off the engine, listen to how each nozzle works. During operation, the nozzle makes a clicking sound caused by the opening and closing of the nozzle.
If there is no stethoscope, then you can use a screwdriver or just put your finger on the nozzle and feel that the nozzle is working.
If the noise of the working nozzle is not audible, then you should check the supply of voltage to it, as well as its resistance and tightness.
Checking the power and resistance of the injector
3. Check the voltage supply to the injector. To do this, disconnect the injector power plugs and connect a control diode lamp to both pins of the plug. Have an assistant run the starter. The LED light should flash.
If the diode lamp does not blink, then the power wire may be broken, or the cause of the injector failure may be a defect in the control unit.
4. Turn off the ignition.
5. Connect an ohmmeter to both pins of each injector plug and measure the resistance of each injector. If on one of the injectors the resistance does not correspond to the nominal values, then this injector should be replaced. The nominal value of the injector resistance is 13.5-15.5 ohms.
Injector leak test
6. Remove atomizers from a distributive fuel highway. Do not disconnect fuel lines and valves from the line.
7. Connect the power wires to the injectors.
8. Lower the nozzles into a suitable measuring container.
9. Have an assistant operate the starter for a few seconds and compare the shape of the fuel jet from each injector. The jet of fuel from each nozzle must have a conical shape, which must be the same for all nozzles.
10. Turn off the ignition.
11. Disconnect the power wires from the injectors.
12. Turn on the ignition for about 5 seconds. Do not engage the starter.
13. Check the tightness of the nozzles. No more than one drop of fuel should flow out of each nozzle per minute.
14. Reinstall the nozzles.