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Fuel Injector Coil Test (W/J39021 or W/Tech 2)



Fuel Injector Coil Test

Verify the resistance of each fuel injector with one of the following methods:

* If the engine coolant temperature (ECT) sensor is between 10-32°C (50-90°F), the resistance of each fuel injector should be 11-14 ohms.

If the injectors measure OK, perform the Fuel Injector Balance Test-Fuel Pressure Test. Fuel Injector Balance Test-Fuel Pressure Test
If not within the specified range, replace the fuel injector.

* If the ECT sensor is not between 10-32°C (50-90°F), measure and record the resistance of each fuel injector with a DMM. Subtract the lowest resistance value from the highest resistance value. The difference between the lowest value and the highest value should be equal to or less than 3 ohms.

If the difference is equal to or less than 3 ohms, refer to the Fuel Injector Balance Test-Fuel Pressure Test for further diagnosis of the fuel injectors. Fuel Injector Balance Test-Fuel Pressure Test
If the difference is more than 3 ohms, add all of the fuel injector resistance values to obtain a total resistance value. Divide the total resistance value by the number of fuel injectors to obtain an average resistance value. Subtract the lowest individual fuel injector resistance value from the average resistance value. Compute the difference between the highest individual fuel injector resistance value and the average resistance value. Replace the fuel injector that displays the greatest difference above or below the average.

Important:
* DO NOT perform this test if the engine coolant temperature (ECT) is above 94°C (201°F). Irregular fuel pressure readings may result due to hot soak fuel boiling.

* Verify that adequate fuel is in the fuel tank before proceeding with this diagnostic.

* Before proceeding with this test review the User Manual CH 48027-5 for Safety Information and Instructions.